This page contains brief summaries of all Lessons in the Main Story.
We are pleased to inform you that you have been accepted at the Royal Academy of Diavolo.
Please return this letter with your sign to confirm your participation.
We are looking forward to welcoming you as part of our new exchange program.
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This tale starts with a dream... your dream.
Please help me. I was locked up by a demon.
You are my only hope, help me get out of here.I beg you, you must find me."
You hear the distant voice of an unfamiliar man and wake up to find yourself in a place that looks like a courtroom. The stern voice of the man in the seat of the chief echoes.
"We welcome you, human, to the demon student council."
You are selected to become a student at RAD, a school for demons.
Awaiting you are seven demon brothers each with their own peculiarities...and a mountain of tasks?!
There is only 1 rule you have to remember...One Master to Rule Them All!
MC awakens inside a strange room that looks similar to a courtroom, where they are greeted by Lord Diavolo, the ruler of the Devildom. Diavolo welcomes MC to the Royal Academy of Diavolo, a.k.a. RAD. MC is also introduced to Lucifer, the vice president of the student council and Diavolo's right-hand man.
Lucifer explains to MC that Diavolo believes demons should start strengthening their relationship with both the Human World and the Celestial Realm. To this end, MC is one of four exchange students being welcomed to RAD; two of which came from the human world and another two from the Celestial Realm. Their period of stay is one year, and students are expected to work on the tasks received from RAD. MC will also be expected to write a report about their experience in the exchange program after the year is up.
MC is then given a D.D.D.: the Devildom's equivalent of a cellphone. Lucifer instructs MC to call his brother Mammon, who is the Avatar of Greed. Despite hating the idea of being put in charge of the human exchange student, Lucifer's threats convince Mammon to come to the assembly hall. MC is then introduced to Lucifer's other brothers: Asmodeus, the fifth eldest and the Avatar of Lust; Satan, the fourth eldest and Avatar of Wrath; and Beelzebub, the sixth oldest and Avatar of Gluttony. Lucifer states that there are seven brothers, of which he is the eldest. Mammon, the second oldest, will be joining them soon. Diavolo explains that the brothers will keep MC safe and that they will be staying with them in the House of Lamentation.
Mammon arrives at the assembly hall and is ordered by Lucifer to be in charge of MC during the duration of the exchange program. Lucifer also states that MC would not be doing their tasks alone, for they do not possess any magic. The tasks consist mainly of dance battles and using the powers lent by the brothers via special cards, which can be summoned through the app in their D.D.D. called Nightmare. Mammon is then told to take MC to the House of Lamentation, which he does.
The House of Lamentation is a dorm reserved for the student council members. As Diavolo has his own castle, he does not live there. MC encounters Leviathan, the Avatar of Envy, and the third oldest brother, who gets into an argument with Mammon over the latter owing him money. Mammon uses MC as a distraction so that he can escape.
Leviathan then drags MC to his room, where he is revealed to be a huge otaku. He is also a fan of the series The Tale of the Seven Lords (aka TSL), and goes on a rant about the series. Afterward, he explains to MC that he lent Mammon money and wants him to pay it back. He advises MC that a human can make a pact with a demon and bond him into service. If MC does so, they can order Mammon to give Leviathan his money back. He then explains to MC his plan on how to make a pact with Mammon through the use of some leverage.
At RAD, two passerby demons gossip about MC, who crosses paths with Solomon, the other human exchange student. He hands them their dropped D.D.D. before heading to class. Lucifer shows up after, and remembering Leviathan's advice, MC discreetly asks him about the whereabouts of Mammon's credit card, Goldie. Lucifer gives MC a hint as to where Goldie might be, which (in the hard lessons) causes quite a bit of discussion between Solomon, Asmodeus, and Satan.
That night, Leviathan messages MC to come to the kitchen because he has a hunch about where Goldie's hidden. Beelzebub is eating in the kitchen as per usual, and MC asks him about the only brother they haven't met; the seventh. Beelzebub warns MC to never mention him in front of Lucifer, then leaves as he's already eaten all the food in the kitchen. Leviathan comes out of hiding and finds Mammon's credit card in the freezer, but Mammon shows up. After he sees Goldie, he begs Leviathan to give Goldie back. Leviathan replies that he'll get Goldie back if he makes a pact with MC, which he agrees to after Leviathan threatens to get Lucifer.
The next day, the brothers laugh at Mammon as well as tease Leviathan, saying that he was won over by MC. Mammon begins to complain about his situation as well as criticize Lucifer, saying this was all his fault. Unfortunately, Lucifer walks into the dining room and overhears this, leading to Mammon's swift punishment. Mammon then stomps off, and when MC follows him he claims that he wouldn't care if MC was eaten by some demon at RAD. MC asks him to stop calling them "human" and start using their name, but Mammon refuses. MC then makes use of the pact for the first time, commanding Mammon to "stay!" The pact freezes him in place, and another command has Mammon using MC's proper name.
Later at RAD, MC meets and chats with Lucifer, Diavolo, and Barbatos, Diavolo's butler. They also meet Simeon and Luke, the two angel exchange students from the Celestial Realm). Both Diavolo and Lucifer make fun of Luke, calling him a 'chihuahua'. Luke retaliates by saying that he reports directly to Michael the Archangel, implying that he is a high-ranked angel. When the conversation ends MC is left alone with Luke, who warns them to never trust a demon, especially when that demon is Lucifer. The first bell rings and they part ways.
That night, MC is in their room when they hear someone calling for help. Attempting to find the source of the voice, they come to a staircase. However, before they could climb the stairs, Lucifer appears and tells them to go back to their room. The lesson ends with MC's flashback on Luke's words to never trust a demon.
The following night, MC tries once more to visit the staircase, only to again be blocked by Lucifer. He emphasizes that MC should not try to go up again. MC comes to the conclusion that they would not be able to reach the top of the staircase unless something is done about Lucifer.
The next morning, Mammon eats breakfast with MC and talks about how much he would like to eat MC. He then goes on to criticize his brothers, commenting things like Leviathan's haircut is lame and Satan's horns look stupid. He refuses to leak any information when MC asks him what was at the top of those stairs. MC then taunts and makes fun of Mammon, until finally, he reveals that Lucifer could be distracted with a vinyl edition copy of the TSL soundtrack, which Leviathan owns. MC uses the power of their pact to drag Mammon to Leviathan's room to get the soundtrack.
As MC and Mammon discuss how to get into Leviathan's room, Solomon appears, saying he was invited by Leviathan to his room. He manages to enter Leviathan's room using a secret phrase as proof that he's a TSL nerd, leaving MC and Mammon outside. Later that night, MC, Mammon, and Beelzebub (who's only there for the popcorn) have a 'TSL Full Series DVD Marathon Night' that lasts for 12 hours. The next day, MC will compete with Leviathan to see who is the biggest TSL fan.
Before that, MC meets Beelzebub and Satan, who both give them tips on how to win. Beelzebub suggests working Leviathan into a jealous frenzy, and Satan tells MC to ask Simeon about the unreleased contents of TSL. On the day of the competition, Diavolo acts as the judge, Satan as commentary, Beelzebub as a guest demon, and Asmodeus as the host. Asmodeus asks MC easy questions and extremely difficult questions for Leviathan. With both sides at a tie, MC proceeds to pull out their trump card.
If MC went to Simeon for advice, they'll provide a summary of the major plot developments in the as-of-yet unreleased TSL Volume 9. Leviathan thinks that MC is lying, but Diavolo — who has the ability to discern whether someone is lying or not — confirms that MC is telling the truth.
If MC went to Solomon, they'll reveal a single-winged pendant. The pendant is a rare version of the Lord of Corruption's lost wing and was only sold in limited quantities with the release of the first TSL volume. The sight of it sends Leviathan to tears.
Either choice, the trump card works, and Leviathan goes into a jealous frenzy, changes into his demon form, and charges at MC. Mammon tries to save them, but he isn't quick enough. Just as Leviathan's about to strike, Lucifer changes into his demon form and stops him, telling him to go cool off in his room. Without Leviathan to continue the competition, Diavolo declares it a draw. MC is then taken back to their room by Mammon and Beelzebub.
Mammon bandages their injured wrist while the two brothers bicker over how they've been spending a lot of time in MC's room since the movie marathon. Once Beelzebub leaves to get a soda, Mammon tells MC the next time he's going to be the one who saves them. MC then gets a text from Leviathan asking to meet him in the Planetarium.
While MC is gone, Beelzebub catches Mammon searching MC's room for things with monetary value, claiming that he would even sell MC if there was any profit in it. Beelzebub comes to the conclusion that Mammon likes MC so much that he can't help but dig through their things, which Mammon furiously denies.
Despite Diavolo's ruling of a draw, Leviathan considers MC the winner of the TSL competition, and so keeps his promise to enter a pact with them. MC then borrows Leviathan's TSL soundtrack and lends it to Lucifer, who tells MC that he won't leave his room that night. MC finally climbs the stairs and finds someone trapped in the attic. He claims that he's a human like MC and that Lucifer imprisoned him in the attic. He asks for MC's help to free him, telling them that in order to do so, MC needs to form a pact with Lucifer and all his brothers.
The next morning, Lucifer asks MC if something kept them up last night, but lets the subject drop after telling them to just focus on surviving in the Devildom until the end of the exchange program. Later that night, MC lies in bed thinking about what the stranger in the attic said when they receive a message from Mammon telling them to meet him in the kitchen. Mammon finds Beelzebub's custard in the fridge and urges MC to eat it. Whether by choice or forcibly by Mammon, MC does so just before Beelzebub arrives. He asks angrily if Mammon ate his custard, and the lesson ends with him shifting into his demon form.
MC, Mammon and Beelzebub are brought to Lucifer's where he lectures them on what they had done wrong. The kitchen has been destroyed after Beelzebub went on a rampage, and since MC's room was adjacent to the kitchen, their room now lacks a wall. Lucifer tells them that MC will be staying in Beelzebub's room for the time being, despite Mammon's objections.
There are two beds in Beelzebub's room; the left belongs to Beelzebub, and the right belongs to Belphegor, Beelzebub's twin brother. Beelzebub tells MC that Belphegor is in the human world as an exchange student along with another demon named Diaval. He also tells them the brothers used to have a sister named Lilith who had been especially close to Belphegor and him. MC later realizes that the occupant of the attic room is actually Belphegor when they find a portrait of him in the portrait room. That night they return to the attic to confront Belphegor, who admits the truth.
The next morning, MC eavesdrops on a conversation between Lucifer and Beelzebub, and learns that the demon brothers were originally angels in the Celestial Realm, but after ending up in the Devildom Lucifer pledged his loyalty to Diavolo. They also learn that there is tension between the brothers due to Belphegor having attempted to stand in the way of Diavolo's dream. MC decides to help Belphegor in order to resolve this conflict.
Later on, Luke messages MC that he's outside the House of Lamentation and he needs to spend the night in MC's room. As MC's room was destroyed by Beelzebub, Luke has to stay with MC in Beelzebub's room. During breakfast, both MC and Beelzebub eat less than usual, wanting to bring food back for Luke. Beelzebub having uneaten food left on his plate causes a commotion between Mammon, Satan, and Asmodeus. On the way back to Beelzebub's room, he and MC find Luke roaming the hallway and looking inside other rooms because being stuck in Beelzebub's room is boring.
Back inside the twins' room, Beelzebub announces that Lucifer is conducting a surprise inspection. He shoves Luke into a closet to hide him, but when Lucifer arrives and orders the closet to be opened, Luke isn't there. He's still gone the next day, though MC and Beelzebub hide this from Simeon when he asks them to take care of Luke until he's ready to come back to Purgatory Hall. Beelzebub and MC search the house but still can't find him. When they reach the entrance hall, they notice the decorative dollhouse of the House of Lamentation has an extra room in it; a room that doesn't exist.
MC and Beelzebub find a secret room that is a copy of Lilith's room back up in the Celestial Realm. When MC asks Beelzebub to tell them more about Lilith, he describes what happened during the Great Celestial War. Mammon suddenly calls MC and tells them to hurry to the underground tomb, which is where Luke is. Lucifer found him there, and is furious at the sight of Luke holding a grimoire. When MC and Beelzebub arrive, Luke accidentally admits Beelzebub hid him in his closet. Lucifer doesn't give Beelzebub a chance to defend himself, and warns that he and Luke should get ready to face the consequences.
MC decides to step between them, shielding Luke and Beelzebub. A furious Lucifer tells them that they can only save one of them. However, MC says they want to protect both. Outraged by MC's reply, Lucifer prepares to attack MC just as everything fades to black. Later, MC wakes up back in the twins' room to Beelzebub calling their name. They ask what happened, and Beelzebub explains that Diavolo arrived in time to stop Lucifer. Simeon took Luke home, who was shaken up but not injured. Beelzebub is also uninjured.
Beelzebub tells MC that he's the one to blame for what happened before, and asks MC why they tried to protect him and Luke. MC either tells him they acted on instinct or that Beelzebub and Luke are important to MC as they're friends. Beelzebub tells MC he wants to do something for them as a thank you, so MC asks him to make a pact with them. Beelzebub asks why to which MC replies they want to impress Lucifer so they help him make up with Belphegor. Beelzebub agrees that he also wants the two of them to make up.
He later takes MC to Hell's Kitchen to eat, but Mammon and Leviathan tag along. MC explains to all of them why they to make a pact with the brothers, and Mammon and Leviathan decide to help. When they return to the House of Lamentation, Lucifer appears and tells MC that their room has been fixed. On the last night staying in Beelzebub's room, he has a dream about Lilith that's different from the nightmare he usually has.
The next morning, breakfast with the brothers is awkward and uncomfortable. Just as MC is about to head off to class early, Lucifer tells them to meet him in the music room. A conversation occurs and Lucifer apologizes for his actions. Shortly after, in the student council room, Diavolo makes the announcement that there will be a retreat held at the Demon Lord's Castle.
Everyone gathers in the entrance hall to get ready to leave for Demon Lord's Castle. Mammon tells MC that there are scary rumors about the castle, like there being an underground labyrinth, but Lucifer interrupts the conversation. He hurries everyone along, as he wants to get to the castle before the angels and Solomon do.
They do manage to arrive to the castle first, where Diavolo and Barbatos greet them. Solomon, Simeon, and Luke arrive shortly after. When the younger angel spots MC, he hugs them, saying he's really sorry about what happened back in the underground tomb. Barbatos then begins to explain how the retreat will work.
First, there will be a tour of the castle to learn about Devildom history, and then Devildom food will be served made by himself. The next day will have a scavenger hunt, food from the Celestial Realm will be made by Luke, and finally there will be a dance held. On the final day, lunch will be Human World food will be made by MC.
Everyone has assigned rooms, and MC is to share a room with Simeon and Asmodeus. Mammon demands a switch with his brother, but Asmodeus refuses, and everyone separates to put away their things. Simeon and Asmodeus have a conversation where the latter exclaims how lucky he and MC are to share a room with him, and that there can't be someone out there who doesn't love him. Satan then arrives and informs them the tour will soon begin.
When they join everyone again, Mammon accidentally reveals that he, Solomon, and Satan plan to collaborate together, as Mammon wants to steal things, Solomon wants some magical items that belong to the Demon King, and Satan "just want to give Lucifer a black eye." Of course Lucifer overhears, and tells Mammon that he expects him to come to his room later.
The tour guide is a tiny demon named Little D. No. 2, who is one of the Little D.'s that helps MC in their tasks. First on the tour is the portrait of the current Demon King, Diavolo's father. Luke comments he last saw the Demon King at a ceremony over 1,000 years ago, and Diavolo mentions he hadn't seen his father in several hundred years, as he's slumbering at the bottom of the Devildom.
While passing through the stairways, Helene, a witch trapped inside a painting, recognizes Asmodeus. Number Two explains that when Helene was in the human world, Asmodeus seduced her and she betrayed her lover at the time, leading to a war that destroyed an entire country. She uses what magic she still possesses to pull Asmodeus, Mammon, Leviathan, Beelzebub, Solomon, and MC into the painting.
MC wakes up to Solomon's calls and finds out they're alone in an underground labyrinth. Solomon summons Asmodeus using their pact, and the three of them soon find the others being chased by a giant snake that was once Leviathan's pet named Henry 1.0.
The snake pursues them, but Solomon amplifies Asmodeus's power, who then charms Henry 1.0., and he shows them to the exit. Afterwards, they explain to everyone how they escaped while eating Barbatos's delicious food.
Later that night, Mammon shows up in MC's room and wants to have a pillow fight. However, Lucifer arrives and overhears Mammon when he insults him, so he drags him away.
The second day of the retreat arrives. Mammon didn't get any sleep last night due to Lucifer, and the rest of the brothers have fun guessing what Diavolo had said. The itinerary for the day is a scavenger hunt, so each group is given riddles to solve to find a historical item in the castle and take a picture of it. However, with Asmodeus sabotaging things, Luke's group is not able to complete their riddle solving.
Asmodeus eventually leaves so that he doesn't have to hear Satan's lecturing, and MC follows. They try to make a pact with Asmodeus, but he replies that he'll agree only on the condition that they get a picture of Lucifer's sleeping face.
Later, Luke serves dishes from the Celestial Realm that he made for dinner, and MC tries to get a hint of where Lucifer's room is. After dinner, Diavolo transforms the Hall and fills it with guests from across the Devildom for the formal dance. The demon brothers and Diavolo transform into their demon forms. Mammon nervously asks MC for a dance, but then Lucifer appears and tells MC to dance with him.
As Lucifer and MC dance, he asks them what it is they are plotting. He warns MC that if they ever seem to be a threat to Diavolo or his brothers, he will show them no mercy. Solomon then appears and invites MC to dance. He comments that while MC may have pacts with demons, they don't have the power needed to command them. So, Solomon uses a spell to lend MC some of his powers for the next six hours.
Later that night, MC, Mammon, Leviathan, and Beelzebub commence 'Operation Photograph Lucifer Sleeping'. When they enter what is supposed to be Lucifer's room, they find Cerberus instead. Everyone escapes through a door, only to fall back into the underground labyrinth with Henry 1.0.
Using Solomon's borrowed powers, MC summons Asmodeus to again tame Henry 1.0. Like Solomon had before, they use a spell to enhance Asmodeus's charm. Asmodeus comments that MC is both able to draw more power out of him than Solomon ever has, and seems to have more magical power than he does.
When the four return to the castle, Lucifer explains that if someone tried to get into his room without knocking, they're transported straight to Cerberus instead. Even though MC failed to get the photo of Lucifer, Asmodeus is impressed by their magical powers and decides to make a pact with them.
Later that night in their shared room, Asmodeus is fawning over MC when Mammon suddenly appears. Satan, Leviathan, Luke, Solomon, Lucifer, and Diavolo soon show up as well. Annoyed at Asmodeus's proximity to MC, Mammon throws a pillow in Asmodeus's face, starting a pillow fight. Once the pillow fight ends and everyone goes to bed, Diavolo and Lucifer discuss MC's pact-making in the garden, while Satan is caught by Barbatos eavesdropping on the conversation.
The last day of the retreat, everyone but Lucifer and Diavolo — who are still asleep — wake up late in the afternoon, tired from staying up all night for the pillow fight. Food from the Human World is served for brunch, with dishes made by MC, Barbatos, and Solomon. Asmodeus is avoiding eating anything Solomon made, and as each of the others try Solomon's food, they understand why. Despite looking delicious, the dishes Solomon made taste terrible to everyone except Solomon himself.
Returning home to the House of Lamentation after the retreat, Asmodeus asks MC why they want to make a pact with all the demon brothers, to which MC responds that they want to earn Lucifer's respect. Lucifer asks what the point of earning his respect is, and what MC is trying to accomplish. Satan then states that he's decided he will also be making a pact with MC, which starts an argument that results in Lucifer telling Satan to get out of the house. Satan declares that he would be happy to leave, and goes to his room to pack.
Afterwards, everyone except Satan and Lucifer meet up in MC's room, where MC explains the plan to get Lucifer to make up with Belphegor. Beelzebub points out that earning Lucifer's respect won't work if Satan makes a pact with MC just to spite him. MC asks why Satan hates Lucifer, and Mammon explains that after the Great Celestial War, Satan was born from Lucifer's Wrath, and that while they all raised Satan, he was especially influenced by Lucifer.
MC then goes to Satan's room, where Satan is trying to decide which books to take with him. He warns MC of one book in particular, as it's a forbidden book that causes people to switch bodies. He then explains to MC that he is considered the "fourth-born" because the Demon King gave him and his brothers their names after arriving in the Devildom in the order of most to least powerful. While he was the last born of his siblings, he's the fourth strongest.
Satan then tells MC to make a pact with him, but MC disagrees with Satan making a pact just to irritate Lucifer, and refuses. This angers Satan, and he threatens MC, but is stopped by Lucifer. The two begin arguing, and as Satan's wrath grows, books in the room start to fly off the shelves. Lucifer grabs one of them at the same time Satan does, and in a flash of white the two switch bodies.
Satan (now in Lucifer's body) states that the effect of the body switch lasts for several days. Lucifer (now in Satan's body) still insists they go to school like this, for he does not want Diavolo asking questions. He also wants to keep an eye on Satan while he's in his body, so the two decide to stay in MC's room.
Once in MC's room, with Mammon and Asmodeus still present, Lucifer discusses how things will work. Neither he nor Satan are allowed to go into each other's rooms unless the other is present, and each will avoid doing anything that might attract attention while at school.
The next day, Lucifer, Satan, and MC run into Diavolo, who asks why Lucifer didn't visit the assembly hall first thing in the morning. Satan poorly impersonates Lucifer, but Diavolo reveals that he could tell Lucifer and Satan had switched bodies from the start. He then reminds Lucifer that he has to give a speech to the student body the day after tomorrow. Lucifer concludes that if they haven't switched back by then, Satan would have to deliver the speech as himself.
After school in MC's room, Satan — now joined by Leviathan and Beelzebub — continues to mock Lucifer with bad impressions. MC goes out into the hall to find Mammon hanging from the ceiling, and helps him down only after he agrees to help Satan and Lucifer make up.
In Leviathan's room, Mammon shows MC a game named Dogi✩Maji✩Memorium. Anyone who registers to play is actually pulled into the game world. Mammon plans to have Satan and Lucifer work together toward a common goal while playing the game. Lucifer, Mammon, Leviathan, Satan, and MC enter the game.
Once inside the game, MC and the others find themselves in a Human World school. Leviathan explains that Dogi✩Maji is a school dating sim; one character is designated the "heroine" (regardless of their gender), and the others have to increase their favorability score with them. In this case, the heroine role is played by MC. In the end, one of the players go up to the Roof of Legend and profess their love for the heroine. If the heroine accepts, they win the game.
Lucifer and Satan — now in their own bodies — challenge each other to see who will raise intimacy with MC first, and the game begins. One by one, MC interacts with each of the brothers, which affects their intimacy levels.
While MC is busy elsewhere, Lucifer, Mammon, Leviathan, and Satan hold a meeting. They discuss the fact that winning the game isn't guaranteed, so they have a brainstorming session on strategies to best raise intimacy with MC.
On the final day where the players must profess their love to the heroine, Satan apologizes to MC for getting them caught up in a weird business. If MC tells him to wait, they say that Lucifer doesn't see Satan as a child, and that he only behaves as he does because he wants to look good in front of Diavolo.
On the rooftop, instead of a love confession, monsters start appearing all over the school and the game has into an ultra-hard survival fight. Leviathan seems to be excited about the crazy plot twist in a simple dating sim. The last boss appears, and looks like Cerberus, but Satan states that it's not the real Cerberus. Cerberus charges toward Satan and is about to strike, but Lucifer commands Cerberus to sit, and warns him not to harm his brother. Cerberus obeys, and the screen states that the Mission is Complete.
Back in Leviathan's room, Satan and Lucifer again have their bodies switched in the real world. However, the two brothers seem to have an agreement begun to accept one another.
While all of this was happening, back in the House of Lamentation, Asmodeus and Beelzebub are looking for MC. As the two are cleaning up Satan's room, they touch the forbidden book and switch bodies. Beelzebub (in Asmodeus's body) comments how he doesn't feel hungry, and Asmodeus (in Beelzebub's body) states that he feels incredibly hungry and considers eating some of Satan's books.
Before he does so, both brothers suddenly return to their respective bodies. The forbidden book looks worn out, and Asmodeus states that the more it's used, the more worn out it becomes, until it eventually can't be used anymore.
While shopping in the Devildom, Lucifer — who's still in Satan's body — MC, and Mammon speak about the speech Lucifer has to make tomorrow. They then stop at Hell's Kitchen, where Lucifer treats them all to a meal, but afterwards reveals he did so that Mammon and MC are now in his debt.
Lucifer want to go to the Human World and find the witch who created the curse of the body switch in order to lift it. At first Mammon is excited about going to the human world, but then changes his mind once he heard witches are involved, because he's afraid of them.
There is an obstacle in the way of the trip, however: only certain demons can travel to the human world directly. Because Lucifer is in Satan's body, the magic circle that acts as a doorway doesn't recognize him, and so they can't travel. Satan then arrives and decides to help them, as he's in Lucifer's body, which means the magic seal lets him pass. Thus, they travel together.
In the human world, Mammon's attitude changes again and he enjoys himself. At Victoria Station, Lucifer buys four matching keychains for the entire group, which surprises Mammon, even though it was what he wanted. Once they board the train and are in a private cabin, Mammon leaves to find the dining car so he can take a picture of the food and brag to Beelzebub. However, he stumbles into the wrong room, and suddenly gets accused of a woman's murder. Lucifer, Satan, and MC arrive at the scene after hearing the woman's last scream.
The brothers and MC meet Lucas, Sophia, and Noah, who were all in the company of the dead woman, who happened to be Grisella, the witch the group was searching for. Lucifer uses his powers to hypnotize the three humans so that they leave.
Back in their own car, everyone hears the ghost of Grisella, who wants them to solve her murder in exchange for lifting the curse of the body switch. All the demons want to torture the three suspects, but MC wants to find a less violent way. They question Grisella and Mammon, and with the information Mammon gives, they guess who the killer is. As the three humans from earlier gather, the witch warns MC about Lucifer, saying he'll soon lose the trust he puts in them.
Once in front of the suspects, Satan decides to explain MC's thoughts, and then declares that the killer is Noah. He turns out to be right, as Noah says he truly wanted to become Grisella's apprentice, but the witch had refused him. She didn't want to take Noah as an apprentice because she predicted she'd die in the train, which would break the man's heart. Ironically, her refusal is exactly why she was killed.
Back in their car, Grisella keeps her word and lifts the curse of the body switch. Surprisingly, Lucifer asks Satan to still do the speech about the report he's supposed to do tomorrow, and his brother agrees with confidence.
At Ristorante Six, Lucifer proposes a toast with everyone — save Leviathan, who is absent — for lifting the curse that had he and Satan in each other's bodies. Diavolo thanks MC for how happy Lucifer is, and comments that the right choice was made having MC as an exchange student. MC asks Diavolo how they were chosen in the first place, and he explains that Lucifer chose them, while he simply gave his approval.
In a flashback, a conversation between Diavolo, Barbatos, and Lucifer takes place. Diavolo and Barbatos say they are jealous of how Lucifer enjoyed himself in the human world, then Diavolo mentions he's noticed how well MC is getting along with Lucifer and his brothers. Lucifer admits that he trusts MC now, but after he leaves, Diavolo seems worried, and Barbatos suspects that what's about to happen will wound him deeply.
As everyone is walking back to the House of Lamentation, Lucifer asks MC what they and Diavolo were talking about earlier. When they answer, Lucifer states that the reason he chose MC was due to a sudden breeze that scattered the lists, and the list them landed at his feet had MC's name on it. However, he also says that MC is special to him on a personal level. The conversation is interrupted by a call for Lucifer from Leviathan, but when Lucifer picks up, all he hears is a scream before the connection is cut off.
At the House of Lamentation, Lucifer looks for Leviathan in his room, but only finds his D.D.D. laying on the ground. Lucifer then notices that Beelzebub is also missing, so he suggests everyone split up in groups, with Satan and MC together with him. As they search, Lucifer recalls the story about the House of Lamentation. Originally, the house was built in the human world, and a married couple with seven children lived here with their servant.
One day, the oldest son ran into the constable's office with news that their servant murdered his family, then took his own life. The oldest son lived on in the house, eventually dying of old age, despite circumstantial evidence that he could have been the true killer. At some point, the house was given the name "The House of Lamentation."
Once the story is finished, Satan again asks MC to make a pact with him. MC is surprised, but Satan states that he's not asking to make Lucifer angry. He's decided that he won't let what Lucifer does bother him anymore. MC accepts, and now has their fifth pact.
Later on, the three hear screams that sound like Mammon and Asmodeus to Satan. When investigating, he suddenly disappears as well, leaving Lucifer and MC alone. Lucifer suggests they go back to Leviathan's room, and once there, they notice Leviathan's PC is still turned on. Lucifer finds the packaging for the game The Demon House with a description matching what is happening now.
Thinking the game is the cause for the disappearances, Lucifer suggests he and MC complete the game to see what happens. Upon searching for a game guide, it states that in order to complete the game, you must defeat the final boss, whose name is Lucifer. The guide also states that there is a romantic ending where the player and Lucifer fall in love.
MC and Lucifer reconvene in the library, where Lucifer states that the only choice they have is for MC to fall in love with him so they can finish the game. He suggests they start by asking each other questions. When MC asks Lucifer what he thinks of humans, Lucifer suspects the real question is what he thinks of MC. He states that originally, he'd only wanted to make sure MC survived the year, but over time his feelings changed. He asks MC why they made pacts with everyone, and MC finally tells Lucifer they met with Belphegor, which enrages him.
Mammon and the others appear, but when Beelzebub hears about Belphegor being locked in the attic, he and Lucifer argue, leading to Lucifer hurting Beelzebub. Belphegor then appears in the room with them.
Everyone is shocked and confused at Belphegor's appearance. Belphegor confronts Lucifer and things escalate, as Lucifer isn't happy about the situation, and Beelzebub is fed up. In the end, Beelzebub, Belphegor, and MC leave the House of Lamentation.
After leaving, Belphegor laughs at the memory of the look on Lucifer's face, but then asks Beelzebub if it was really okay to leave like that. He answers that he doesn't know, but that they can't go back anymore. He then apologizes for taking MC with them, explaining that he thought it would be dangerous to leave them with Lucifer.
Beelzebub tells MC that the brothers had all gone missing earlier as a practical joke in order to bring Lucifer and MC closer. He then says that sitting and hiding so long has made him hungry, which makes Belphegor nostalgic. Belphegor then comments that he can smell something good, and Beelzebub recognizes the scent of Simeon's BLT devil sandwiches. Sure enough, Simeon shows up, and is surprised at seeing Belphegor. When Belphegor asks him if they can stay at Purgatory Hall, Simeon agrees, but feels like something is going on.
In Purgatory Hall, Beelzebub explains to Simeon, Solomon, and Luke about what's been going on with Belphegor. Solomon and Simeon express disbelief in the entire situation. Belphegor goes on to explain the curse that kept him locked in the attic, which required the power of six of his brothers to break. That why he asked MC to make pacts with everyone.
However, MC explains that they hadn't made a pact with Lucifer, leading everyone to question how the curse was broken. Belphegor claims that he heard a voice, then he found the door was open. Solomon then points out that even if MC had made a pact with Lucifer, it still wouldn't have been enough, as they lack the ability to control the brothers' powers. Simeon then suggests that someone else must have taken Lucifer's place and filled in as the sixth sibling.
Later on, after bribing Luke to let MC, Beelzebub, and Belphegor use his room to sleep in, Belphegor is still relishing in his freedom. Beelzebub tried to press Belphegor for why he was locked in the attic, but Diavolo suddenly appears, and interjects that if Lucifer hadn't locked his brother up, Belphegor might have destroyed the human world.
Both Diavolo and Barbatos enter the room, and explain that Belphegor vigorously opposed the exchange program. He'd attempted to appeal to Lucifer, but Lucifer had supported the program. Diavolo further explains that Belphegor hated humanity and couldn't accept Diavolo's plan for uniting the Devildom, Celestial Realm, and the human world. Belphegor was angry, to the point that he was a threat to the human world, which prompted Lucifer to lock him in the attic for his own protection.
Belphegor becomes angry when Diavolo claims Lucifer was sheltering him, declaring that he was a prisoner in the attic. Diavolo then corrects him, saying Lucifer was indeed protecting Belphegor from him, then has Belphegor arrested for treason. Beelzebub attempts to interfere, but MC stops him. Diavolo warns them both that if they choose to defy him, things will only get worse for Belphegor. He then explains Belphegor will face justice for his actions, and that Lucifer has been placed under house arrest in the House of Lamentation. He then tells MC to stay out of this, claiming it's a demon matter, and as a human exchange student, they have no involvement. Both he and Barbatos then leave, taking Belphegor away.
MC and Beelzebub return to the House of Lamentation with intentions to talk to Lucifer about Belphegor. First, however, goes to Mammon to apologize and ask him for help. Mammon tells MC that Lucifer had locked himself in his room, and to get him out they're going to need as much help as they can get. So, they both go to find Leviathan.
They find Leviathan talking with Henry about how betraying and awful humans are, ignoring MC's and Mammon's presence in his room. Mammon tries to explain that MC's pact with him didn't have anything to do with Belphegor, but Leviathan doesn't believe him. MC makes a TSL reference regarding the friendship between the Lord of Shadow and Henry, leading Leviathan to hug them and call them his true friend.
The trio is then joined by Satan, Asmodeus and Beelzebub, and they all gather in the underground tomb to follow Mammon's plan. He wants MC to touch the grimoire so that Lucifer will leave his room. However, they first need to sneak past Cerberus, who is patrolling the area.
When MC touches the grimoire, they see a flashback of when Lucifer fell into the Devildom with a dying Lilith after the Great Celestial War. Diavolo appears before him, and at Lucifer's request, promises to save Lilith. However, in return for the great risk of interfering with the Celestial Realm's judgment, Lucifer would have to pledge his loyalty to Diavolo. To this, Lucifer agrees.
When the flashback ends, MC tries to pick up the grimoire, but can't because of the ivy covering it. As Cerberus approaches, Lucifer appears and commands him to sit. MC can either hug or hit Lucifer, and both responses surprise him.
MC gathers everyone back into the mansion to talk about Belphegor. Lucifer reveals that he had locked Belphegor away for his own protection, because he was openly against the human race and put Diavolo's exchange program in jeopardy. Belphegor's reason for hating humans stems back to Lilith's death, as he believes that humanity was responsible.
Meanwhile, back in the Purgatory Hall, Luke is worried about MC and Beelzebub, while Simeon and Solomon try to calm him down. Solomon wonders why Lucifer is loyal to Diavolo, and Simeon comments that Diavolo and Lucifer seem like close friends rater than master and servant, or at least Diavolo sees Lucifer like that.
In a flashback of Simeon visiting the Devildom for the first time after Lucifer's rebellion, he finds Diavolo being extremely friendly with Lucifer, to the point Lucifer had to stop him from embarrassing him any further. Solomon's and Simeon's conversation is interrupted by Luke yelling about his burnt cookies.
In one last flashback, Belphegor is talking to himself in the attic when Lucifer appears. He asks if Belphegor has calmed down yet, reminding him that he was meant to use the time in the attic to rethink what he'd said earlier. Belphegor responds that he'll be stuck here forever, because he'll never change his mind.
Lucifer tells him they're chosen the second student from the human word, and that they are an average, non-magical human. Belphegor threatens to tear them to shreds, ruining both the exchange program and Diavolo's reputation. Lucifer tells him that won't happen, because the door to the room can only be seen by demons, and the stairs are cursed so that no demon but Lucifer can climb them.
After Lucifer's explanation as to why Belphegor was locked in the attic, MC asks why he hates humanity in the first place. The brothers explain that, as an angel, Belphegor loved humans and often visited the Human World in secret. His visits led to their sister and youngest sibling — Lilith — also being interested in humanity, and eventually to her falling in love with a human. Unfortunately, the man was stricken with an incurable illness, and in an attempt to save him, Lilith gave him forbidden food from the Celestial Realm.
Because altering the lifespan of a human is forbidden, when caught, she was sentenced to be wiped from existence, which of course Lucifer and his brothers refused to accept. Their rebellion turned into what was afterwards called the Great Celestial War. It was a war the brothers lost, and fell into Devildom, becoming demons.
Belphegor blamed the man Lilith had fallen in love with, and argued that she wouldn't have died if neither he nor humanity as whole had never existed, so he began hating humans. However, Lucifer also reveals that Lilith did not die at the end of the war, but was instead saved by Diavolo and reborn as a human, which is why Lucifer swore his loyalty to him.
After hearing all of this, MC and the brothers decide to pay Lord Diavolo a visit. They ask Diavolo to release Belphegor, to which Diavolo eventually agrees, but only under the condition that MC travels back into the past and ascertain exactly who it was that freed him from the attic.
With the help of Barbatos, MC returns to the time when the brothers were pretending to disappear. After being spotted by them, they explain that their plan was to get Lucifer and MC alone together to make up. The brothers urge MC to go back to Lucifer and patch things up, so MC leaves. They arrive outside Leviathan's room to hear Lucifer complaining about how ridiculous the game is, then nearly run into both him and their past self.
To avoid being seen by their past self, MC hides in the hidden replica of Lilith's bedroom. They start seeing disconnected events of the past, including an argument between Lucifer and Belphegor about the exchange program. MC heads to the attic to find the door to Belphegor's room missing, but after touching the wall where it should be, the door magically opens.
They enter the room, and Belphegor overwhelms MC with his appreciation upon realizing that he is free. However, suddenly he turns into his demon form, and mocks MC for falling into his trap. He then attacks them, intent on ending the exchange program by killing MC.
MC faints from the pain, and they hear the voice of Lilith in a dream-like world. Lilith explains she no longer has a physical form, but after her death as a human, she recalled her memories of her past life. Since then, she'd been watching over her brothers as a soul. Lilith then lends MC her powers so that they can save her brothers.
In the timeline MC left, the brothers anxiously await MC's return, minus Lucifer and Beelzebub, who visit an imprisoned Belphegor only to find him sleeping. Lucifer apologizes to Beelzebub for lying to him about Belphegor being in the Human World, and Beelzebub tells Lucifer he can make up for it by trusting his brothers more.
Back in the past, MC wakes up completely unharmed. They hear an argument downstairs, and head to the source to find a duplicate of themself dying in Mammon's arms. The brothers are panicking, horrified at the idea of MC dying, when they spot the future MC standing there. After a moment of confusion, the MC in Mammon's arms disappears. Belphegor begins to attack MC again, but stops when MC tells him about what really happened with Lilith.
Lucifer asks where MC heard that story from, and Diavolo enters the scene to reveal that MC is a distant descendant of Lilith's. He asks MC if they ever had visions of Lilith's memories, and MC recalls the memory of Lucifer pledging his loyalty to Diavolo. Diavolo then postulates that some of Lilith's angelic powers and memories remained even after being reborn a human, and both had passed on through her descendants.
The brothers are overjoyed both that MC is alive and well, and to learn that their sister lived a happy life that resulted in MC being here with them now. Belphegor apologizes, and finally admits the truth; he blamed himself for Lilith's death, but tried to escape his feelings of guilt by blaming humanity instead. Lucifer responds that Lilith's death wasn't his fault, and that he should've told him that sooner.
Some time afterwards, the brothers — including Belphegor — are fawning over MC. MC asks Barbatos about their disappearing double, and he tells them another power of his: he can choose from any number of potential realities and make his choice the sole reality. Because the reality he chose was one where MC was never harmed, the other MC disappeared, having no longer ever existed.
In a flashback, Lucifer is buried in paperwork for choosing the second human exchange student. Diavolo suggests choosing a human completely different from Solomon, but when Lucifer decides to take a break and open a window, a gust of wind sends the paperwork flying everywhere. The paper that landed at his feet has MC's name on it, and Lucifer decides they will be the second human student. Diavolo states that nothing is a coincidence in this world, and agrees with Lucifer's decision.
The brothers are having breakfast as usual, but when Belphegor enters, things get awkward. Leviathan announces that he's going to grab his food in the cafeteria. Beelzebub, Satan, Mammon and Asmodeus come along. Asmodeus questions MC whether they are coming along too, to which they can either agree, or say that they'll wait for Belphegor. Lucifer then enters to announce Diavolo's birthday party, and everyone heads to RAD.
Belphegor notices his brothers' wariness of him, as does MC, so Simeon suggests MC "serve as a bridge" for the brothers. After school, MC goes to the planetarium with Belphegor, and asks them what they were planning on giving Diavolo for his birthday, but they're interrupted by a loud noise coming from the music room.
They catch Mammon rummaging through the room, and Belphegor accuses him of stealing. Mammon retorts that he wants to give someone a present. Belphegor asks if the present is for Diavolo's birthday, and Mammon seems to suddenly remember that's coming up soon, but agrees that the present is for Diavolo. Belphegor changes the topic to getting money for Diavolo's present. He suggests working in Hell's Kitchen, which the three decide to do.
Afterwards, Leviathan meets up with MC, and says that Belphegor wants to play games with him. He worries that it would be awkward, so he tells MC to give Belphegor the message that he's busy waiting to accept a package from Akuzon. MC leaves for the twins' room and gives the message, but Leviathan shows up to say the package had been delivered, so he brought some games with him for all three of them to play. Belphegor falls asleep in the middle of gaming, to which Leviathan seems surprised and slightly disappointed, but then comments that he shouldn't have worried about things being awkward.
Later, MC and Belphegor are playing card games, with Belphegor repeatedly losing. Lucifer then enters, and wants to talk with Satan about Diavolo's birthday. Satan agrees, and the two leave. Belphegor notes that Satan was acting strangely agreeable with Lucifer, and asks MC if they know anything. MC tells him about the forbidden book incident, and how Satan and Lucifer's relationship changed.
After the story, Belphegor says wishes he'd been there. Satan returns and overhears them, then comments on how he still loves to see Lucifer suffer. Belphegor then suggests forming "The Formerly Anti-Lucifer League" with the goal to make Lucifer's life as hard as possible. The three adjourn to the library to discuss the group's first prank: putting hot sauce in Lucifer's prized vintage Demonus.
Said Demonus is kept in Lucifer's study, which is behind a secret door in the library. They assume a secret code or phrase is needed to lift the enchantment and open the door, so start trying taunting phrases to get the door open. Unfortunately, they are caught by Lucifer, who tells them to come with him for a stern talking-to.
MC and Belphegor are out shopping for Diavolo's birthday present, when Solomon appears, and tells Belphegor he'd like a pact with him, He notices that Belphegor glances in MC's direction, then declines his offer of a pact. He and MC then head back to the House of Lamentation, where Asmodeus comes along and drags them both to his room. He asks MC what sort of outfit they like, then reveals that the outfit is for MC, but Belphegor then pulls MC out of the room.
Later, MC, Leviathan, and Mammon are playing a video game in MC's room, but Belphegor interrupts them after a fight with Beelzebub. He tells them that it was because Beelzebub was feeling guilty due to not knowing Belphegor was being held prisoner. Belphegor asks MC if he can sleep in their room, but Mammon aggressively declines, and offers to help Belphegor and Beelzebub to make up.
When MC and Mammon search for Beelzebub, they find him in the kitchen cooking soup for Belphegor. The three take the soup back toward MC's room, and Beelzebub worries whether or not Belphegor would forgive him. Leviathan and Belphegor come out of MC's room, and Belphegor, tired of Beelzebub's behavior, slaps him, and says firmly that what happened wasn't Beelzebub's fault. The two are then able to make up.
After a day of school, Lucifer invites MC to go shopping with him for Diavolo's present, and then the two have dinner at Ristorante Six. Lucifer raises the topic of MC helping Belphegor and his brothers patch things up, and thanks MC for helping them. Then then return to the House of Lamentation to find Belphegor, and Lucifer invites him as well as MC to come with him and provide an opinion.
He leads them to Lilith's room from the Celestial Realm, and confesses that he created the room to never forget Lilith, but the secret of Lilith's reincarnation had been too much too bear, so he'd unloaded it all here. He says that he doesn't need the room anymore, but wants Belphegor to use it if he needs it. Belphegor says that he also doesn't need the room, but thanks Lucifer for being able to make the decision, and the two make up.
At the Demon Lord's Castle begins, Diavolo's party begins, but he reveals in a speech that the party is meant for MC too. The brothers all give MC their gifts, but Belphegor is nowhere to be seen. MC finds him in the garden, where admits he wasn't sure what to give MC, so he decided to give himself. He makes a pact with MC, and then Asmodeus, Beelzebub, and Mammon find them, and urge them to go back to the party.
In a flashback before the party, the brothers are in Lucifer's private study, where he announces his idea of making Diavolo's birthday party also be a welcome party for MC. Asmodeus decides to buy a present for MC, so the others decide to do the same. Belphegor raises the idea that he should give MC himself by making a pact with them. The other brothers each try to subtly ask MC what they would want as a gift.
After the birthday/welcome party is over, Beelzebub and Satan are playing chess in the music room with MC and Belphegor. Lucifer then enters, and tells Belphegor that he has to make up for all his missed classes. He gives Belphegor all of his assignments, and tells Beelzebub and Satan not to help him.
Later, Belphegor is studying in the twins' room with MC helping, when one by one Mammon, Asmodeus, Satan, Beelzebub, and Leviathan each enter the room. They all try to help Belphegor in their own ways, but are mostly just distracting. Belphegor finally snaps, and takes MC with him to his attic room. He thought he could now focus on his schoolwork, but instead falls asleep on MC's shoulder.
The brothers are once again having breakfast, and as Beelzebub eats Leviathan's meal again, everything in the Devildom seems back to normal. Belphegor enters as the room, and Mammon comments that he woke up even later than Leviathan. Lucifer then also enters the room, and asks MC to join him tomorrow for a meeting with Diavolo discussing the end of their stay as an exchange student. The room is filled with silence, as all of the brothers are upset.
Breakfast ends, and everyone is getting ready to head to RAD. Lucifer requests MC stay behind, and tells them his brothers are sad that MC's leaving, so he wants MC to spend as much time with them as they can. Once classes are over, Mammon invites MC to hang out, but Leviathan interrupts, demanding Mammon give his money back. Mammon makes a break for it with MC, but Leviathan is close behind.
Still being chased, MC can either suggest hiding in Mammon's room or Leviathan's room. If MC suggests Mammon's room, they'll hide in the trunk of his car. If MC chooses Leviathan's room, they hide in Leviathan's bathtub he uses as a bed. Leviathan enters, then tells Henry that he's sad MC is leaving next week. He eventually leaves the room, and MC and Mammon leave as well.
The two make it out of the House of Lamentation and get some distance between themselves and Leviathan. Mammon laughs about the look Leviathan had on his face as they escaped, then questions MC about staying in the Devildom. However, Leviathan has caught up to them, so Mammon runs away. Leviathan, tired of chasing him, and admits that he too, wants MC to stay in the Devildom.
The next day, the scheduled meeting takes place in the Student Council Room. Diavolo states that Lucifer seemed distraught over MC going back to the Human World, and that he's also sad about MC leaving. Once school is over, MC is spotted by Asmodeus, who invites them to hang out. The two go to Hell's Kitchen, where Asmodeus challenges MC to a drinking contest.
The contest involves drinking Demonus — a common alcoholic Devildom beverage — which turns out to have no intoxicating effect on humans. Because of this, MC wins the drinking contest, which leads to a drunk Asmodeus hugging MC with tears in his eyes as he asks them to stay in the Devildom. Satan finds them like this, and carries Asmodeus back to the House of Lamentation.
He puts Asmodeus to bed and returns to his room, where MC was waiting. He has something to ask MC, and starts talking about a book of old folktales he recently acquired from the human world. In one story, a king is given aid in winning a war by a beast with magical powers. The king then kills the beast, who turns into a monster and curses the entire country. To end the curse, the king offers his newborn daughter as sacrifice. Twenty years later, the daughter is seen still alive, and people try to kill her out of fear. The monster appears and saves her, giving up his own life.
Satan asks what MC thinks the beast felt in its dying moments, and then wonders in confusion what it is he's feeling for MC now. He says that he knows MC returning to the Human World doesn't mean they'll never meet again, but the thought of them not being around still makes him sad.
MC is at RAD chatting with Simeon, Luke, and Solomon about leaving the Devildom. Solomon suggests they should all meet up again someday, and everyone agrees. After school at the House of Lamentation, MC finds Beelzebub searching for Belphegor, and helps look for him.
Eventually, MC and Beelzebub find Belphegor sleeping in the attic room. Beelzebub is relieved to find him, then thanks MC for bringing their family together. Belphegor then wakes up, and Beelzebub admits to Belphegor his worries about him running away. Belphegor tells him not to worry, and Beelzebub heads for the kitchen.
After Beelzebub's gone, Belphegor suggests that he, Beelzebub, and MC live together, but then admits what he's asking is selfish, because MC has a life in the human world to return to. Beelzebub then returns with a mountain of snacks, followed by Mammon, Leviathan, Asmodeus and Satan. A going-away party begins, but after awhile MC leave to find the door to Lucifer's secret study is open, and music plays within.
MC goes inside to find Lucifer listening to the cursed vinyl edition of The Tale of the Seven Lords soundtrack. Lucifer notes that he chose MC as the exchange student in this room, and that while there were times he thought he'd made a mistake, he's now certain he made the right choice. He asks MC if they finished everything they set out to do in the Devildom, and MC answers that they haven't made a pact with him yet. Lucifer then turns into his demon form to intimidate MC, and asks if they still want a pact with him. Regardless of MC's answer, Lucifer still makes the pact.
On the final day, Diavolo, Barbatos, the seven brothers, and the exchange students are is gathered in the Student Council Room, where said exchange students will be sent back to their own worlds. Simeon, Luke, and Solomon leave first, after saying their goodbyes. Diavolo gives his farewell to MC, followed by each of the brothers, before MC returns to the Human World. MC then gets a message from Solomon informing them they can still use their D.D.D. in the human world.
Some time later, Barbatos serves Diavolo tea that he procured from the human world, which makes Diavolo think of MC. Barbatos notes that it has been quite a while since MC left, yet everyone is still in low spirits. He questions whether Diavolo is unhappy. Diavolo admits he might be, then asks Barbatos if he's sad his baking partner Luke is gone. Barbatos answers that he is.
At the House of Lamentation, Leviathan and Mammon are arguing over money Mammon owes, to which Lucifer threatens Mammon with hanging him upside down. Satan complains that he was hoping for someplace quiet to read his book, then Asmodeus starts complaining that Beelzebub ate his special sweet he wanted to post about on Devilgram. He wishes MC were there, and Leviathan agrees that they'd find a way to fix everyone's conflicts.
Belphegor then enters, and comments that the room feels somber before asking if anyone had seen his D.D.D. He says today is the day MC calls him, which fills the others with shock and jealousy. Everyone then hears Belphegor's D.D.D. ringing.
In the Devildom, Solomon tells MC to take a dagger and thrust it into someone's chest, but MC's vision suddenly goes black. They regain awareness back in the Human World to the sound of their D.D.D. ringing. The call is from Mammon, who asks how MC is doing, then complains that Lucifer insisted the brothers take turns calling MC.
He has to hang up shortly after, as Satan is calling him to go to a Student Council meeting. Afterwards, MC gets a text from Solomon, but in the middle of the text conversation, he shows up in person. He tells MC that they need to "get going" and uses his magic to teleport them both to the Devildom.
In the student council room at RAD, a meeting is being held. However, all of the brothers — minus Lucifer — are instead talking about whose turn it is to call MC next. Suddenly, Solomon and MC appear. Everyone is surprised, including Diavolo and Barbatos. Belphegor asks MC if they're staying for a while, but says that their room at the House of Lamentation is covered in dust, so Beelzebub suggests that MC stay in the twins' room instead.
An argument breaks out over where MC will stay, but Diavolo interrupts. He tells MC he's happy to see them, but that they were in the middle of an important meeting. Lucifer gives MC a key to the house, and tells them to wait there.
Solomon escorts MC to the House of Lamentation, then heads for Purgatory Hall. The brothers return home shortly after, and Lucifer complains about everyone losing their composure as soon as MC showed up. The others point out that Lucifer wasn't any different, which is why Diavolo ended the meeting early.
At dinner, Leviathan comments that the soup Mammon made tastes strange. The others agree with him, including Mammon himself. Leviathan then changes the subject, because he wants to show MC the bottle of Gold Hellfire Newt Syrup he recently bought. However, the bottle is empty, and Mammon admits it's because it was the secret ingredient he used in the soup.
Leviathan is furious, and says that syrup was an expensive item modeled after a remedy within the The Tale of the Seven Lords universe. Satan asks Leviathan what the syrup's effects are, and his face suddenly turns red. He then tells MC to stay away from his room, then runs away.
MC and Satan meet up in the library, where both were looking for more information on what the syrup does. Satan says he knows a book that probably has the information, but can't find it in the library, so the two go to his room to look there. They eventually find the book, which says that when consumed by demons, Gold Hellfire Newt Syrup is a potent aphrodisiac, though this heightened sexual desire is felt towards humans only. It's possible to neutralize the effects if the demon carries out an order issued by a human they have a pact with.
After reading the book, MC gives Satan an order to either hug them, kiss them, or meow like a cat for them. Satan obeys, and the effects of the syrup wear off. He then warns MC that the syrup is very powerful, and that they should make sure none of his brothers find them.
MC leaves Satan's room and runs into Beelzebub, who seems to be acting normal. He asks MC if they want to come with him to the kitchen. Once there, however, the syrup starts to take an effect, and he asks MC if he can nibble on them. MC grabs a cream puff for him instead, but said cream puff belongs to Belphegor, who cursed it so that it explodes when picked up.
Whip cream covers MC, who can order Beelzebub to clean it off their lips, their hand, or to grab them a towel. Beelzebub obeys the order, and the syrup's effects disappear. Belphegor then enters the room, angry that his cream puff was touched.
In a flashback before the meeting began, Simeon texts Lucifer from the Celestial Realm to ask him how things have been, to which Lucifer answers they are "the same as ever." Luke enters the room looking depressed, and Simeon asks if it's because Luke misses the Devildom. Luke dismisses the idea, then Simeon gets a text from Solomon telling him that he's in the Devildom with MC.
An angry Belphegor storms off, and Beelzebub urges MC to chase after him. MC finds Belphegor on the stairs to the attic, and he admits he can't be around them because the Gold Hellfire Newt Syrup has started to take effect. He goes up to the attic, and MC follows. Belphegor says that if MC wants to be forgiven, they have to do whatever he wants, so MC gives Belphegor a massage. MC suddenly starts tickling Belphegor, who tickles MC back. When MC tells him to stop, it counts as an order and the syrup's effects fade.
Back out of the attic, MC encounters Asmodeus in the hallway, and he accidentally pushes MC to the ground. MC tells Asmodeus to get off them, which he does, but then he starts wheezing. MC helps Asmodeus to his room, where he says that he's going to die from the tightening in his chest, so he gives MC a last request: to put their arms around him. When they do, he gives up the act, and tells MC that the effects of syrup were already cancelled when MC ordered him to get of them.
Lucifer then enters the room, and gives MC a package that was addressed to Leviathan, but was sent to his room instead. Asmodeus ask Lucifer how he isn't affected by the syrup, and Lucifer answers that something like that would not affect him. MC leaves and knocks at Leviathan's door. Leviathan asks for the secret phase, which begins with "The second lord..."
MC then enters, but Leviathan asks them to not come any nearer. However, he can't keep himself from throwing his arms around MC and admitting that he missed them every day. He asks MC to give him an order, which they do. Mammon then starts texting MC a bunch of emoji spam.
MC goes to see Mammon, who's angry at MC for going to his brothers first instead of him. He admits that he has been thinking of MC as much as he's been thinking of schemes to make money. MC can order Mammon to kiss them, hug them, or shake like a dog, to cancel the effects of the syrup. Diavolo then texts MC to tell them that he's arranged for their stay in the Devildom.
Lucifer also texts MC, asking them to come the library and sign some papers for their stay in the Devildom. Once finished, he asks MC to give him the papers, but blushes when their hands touch. He finally admits that he's been hiding how much the syrup is affecting him, and asks MC to give him an order. MC can order Lucifer to kiss them, hug them, or tell him to stay. Lucifer obeys the order and is cured, but they suddenly hear screams. Asmodeus enters the room, and says Leviathan had another bottle of the Gold Hellfire Newt Syrup that Mammon tried to steal, which led to a fight, and now both of them are covered with the syrup.
In the Celestial Realm, Luke is still behaving depressed and denying it. Simeon asks if he wants to see MC and Solomon, then suggests inviting them both to visit the Celestial Realm. Luke races off to ask Michael about it, and Simeon texts Solomon to ask him why he suddenly brought MC to the Devildom. His answers are evasive, so next Simeon texts Lucifer about it. However, at the time of his texting, Lucifer is still under the influence of the Gold Hellfire Newt Syrup, so he can't focus only anything other than wanting to see MC.
Luke and Simeon text MC to invite them and Solomon to the Celestial Realm. MC asks Diavolo at RAD about it, and he explains that MC being a short-term exchange student in the Devildom doesn't prevent them from visiting the Celestial Realm. When news reaches the brothers — minus Lucifer — at the House of Lamentation, everyone wants to go with MC. Mammon suggests MC draw a card, and the number they pick will represent who gets to go with them.
MC picks Mammon's number, but it's discovered that all of the cards are identical. Lucifer enters, and tells his brothers to forget about going to the Celestial Realm. Solomon then texts MC to tell them he's heading to the Demon Lord's Castle, and will see MC there. Everyone bids MC farewell, and Lucifer escorts them out.
Once at the castle, Lucifer bids MC goodbye, and both they and Solomon follow Barbatos to the garden, where the gates of the Celestial Realm open for them. After the two arrive, Solomon mentions that it's his second time visiting the Celestial Realm. A voice calls out to them, and both Luke and Simeon arrive.
Luke tells MC that Michael wanted to meet them, but Simeon explains it wasn't possible due to a sacred spring starting to dry out. Solomon mentions that both Luke and Simeon will be coming back to the Devildom with MC and him as part of a short-term program. Both MC and Luke had no idea, and Luke is upset that Simeon didn't tell him. The four of them all return to the Devildom.
Once again at RAD, Lucifer announces that there will be a student council meeting, and that MC needs to be there as well. The meeting is about the upcoming school festival, and Diavolo selects MC to head the committee. The first task is to decide what will they do for the event, wants MC to have suggestions ready for the next meeting. Diavolo tells Lucifer he notices they're one officer short before departing.
The missing member is Belphegor, and a furious Lucifer orders everyone to find him. Lucifer has too much work to do for searching, and so does Leviathan, Mammon and Satan. Asmodeus, Beelzebub, and MC search for Belphegor, but he's nowhere to be found. The search continues at the House of Lamentation, where Asmodeus splits off, but Beelzebub and MC stick together. After searching several places and not finding him, Beelzebub searches his and Belphegor's room and suggests MC search somewhere else.
MC enters the attic and finds Belphegor just waking up. He jokes that if he knew it was them, he would've kept sleeping so that MC would kiss them awake. Beelzebub and Asmodeus then enter the room, and Asmodeus reminds Belphegor that he missed the student council meeting. They all go downstairs, but instead of reaching the library like they should have, they're in the music room. Belphegor notes that he doesn't have any signal on his D.D.D., and everyone wonders what is going on.
After trying to go through many doors in the House of Lamentation, it's discovered by MC, Asmodeus, Beelzebub, and Belphegor that none of the doors lead outside. They wind up in the kitchen, where Beelzebub's finds a cake that looks like an anime character Leviathan likes. Just as he's about to eat it, Leviathan appears to protect it. Thankfully, the next door opens to outside the house. Levi informs the rest that he forgot to turn off his new 3D escape game, which was the cause for the door phenomenon.
Some time later, Belphegor finds MC in their room and shows them the pile of work Lucifer gave him as punishment for missing the meeting. He tells MC he's getting hungry — due to not being allowed to have dinner — and asks if MC would come with him to get a snack. They find the kitchen door locked by a spell, so they head for the Planetarium instead.
Belphegor asks MC if they are okay with Diavolo assigning them to lead the festival committee, then says he thinks that Lord Diavolo is self-centered. Eventually, Belphegor and MC both fall asleep, and Lucifer punishes Belphegor the next morning by not letting him eat breakfast because he didn't complete his assignments.
MC and Belphegor are still together at RAD when Diavolo walks in to tell MC he wants them at the student council meeting later. Belphegor tells Diavolo it's annoying how he makes decisions on a whim, to which Diavolo says he understands how Belphegor feels, then hands him an energy drink made by Barbatos.
MC follows Diavolo out to find him puzzled about the door leading to the wrong location. MC explains that they'd borrowed Leviathan's game, and that it must have activated when they dropped it. Diavolo thinks it sounds fun, so they work together to try and get to the student council room.
Along the way, MC asks Diavolo about Belphegor's comments, and Diavolo says he will take what Belphegor said into consideration. The next door they open leads to the colosseum, and Diavolo tells MC the colosseum was here before RAD, but was once destroyed in a war with the Celestial Realm. It's also where he found Lucifer holding Lilith in his arms. He looks sad, and wonders if choices he made to reach this point where the right ones, but then asks MC to ignore what he just said.
The next door finally opens to the student council room, where Mammon and Satan are complaining about how long it took to get there. The meeting about the festival starts now that Diavolo and MC are here, and Diavolo asks MC if they have any suggestions for what the student council should do. Eventually, the group settles on doing a play. After the meeting, Lucifer takes Mammon, Leviathan, Beelzebub, and MC aside to ask who is responsible for the door phenomenon. When he learns the game Leviathan bought is at fault, he gives him a lecture.
Back at the House of Lamentation, everyone is discussing the plot of the play when Satan suggests they ask for Simeon's help. Leviathan asks why, and Satan tells him that Simeon is the author of The Tale of the Seven Lords, rendering Leviathan speechless.
The brothers and MC have a brainstorming session to decide what the play will be about, and MC suggests a fairy tale. Satan and MC then find Simeon and ask him to write the script for them. Simeon agrees, but when starting to work on it after school at Purgatory Hall, he encounters a shocked Luke, who also had no idea that he wrote TSL.
Satan, Luke, Simeon, and MC are at RAD discussing plot ideas for the play. Simeon asks Satan and MC if they have a rough idea of a theme for the play, to which Satan responds, "Prince Lucifer and Princess Diavolo." Simeon exclaims that he loves the idea, and is 100% in on coming up with a story on that basis.
The group builds on this idea, and Simeon asks MC what type of demon the protagonist is, what kind of story the play will be, and how the play should end. The choices MC makes do affect the play in future lessons. The meeting is dismissed, and the next step is to get Diavolo's approval. They find him in the student council room, and he loves the idea. Simeon states that they should go to Leviathan next for costumes.
At the House of Lamentation, Simeon and MC knock on Leviathan's door. He asks a TSL question as a test to get into his room, but is shocked to realize Simeon is there too. The pair enter Leviathan's room to find him standing with his eyes closed because he doesn't think he's worthy to be in the same room as Christopher Peugeot, which he now knows is Simeon's pen name. Simeon asks Leviathan if he would make the costumes for the play, and Leviathan accepts.
At dinner, Lucifer tells Leviathan, Asmodeus to go out and buy the needed materials for the costumes, with Beelzebub and Mammon accompanying them. During the trip, Leviathan, Asmodeus, and Beelzebub end up going off in their own ways, leaving only MC and Mammon together. Suddenly, Little D. No. 2 runs up to Mammon while calling him "Papa." Mammon insists he stop calling him that, and asks what he's doing there.
No.2 explains that he, Diavolo, and Lucifer are investigating an illegal casino — which Mammon pretends not to know about — but he got separated. No.2 asks Mammon and MC to help him find Diavolo and Lucifer, then tells them he last saw Diavolo at the traveling carnival nearby.
At the carnival, a wandering ghost snaps a pic of Mammon and MC and tries to get them to buy the photo. MC can offer to buy the photograph, or No.2 will buy it for them. The group then play a crane game filled with zombie iguana stuffed animals, and Mammon wins one for both No.2 and MC. After MC bumps into Mammon while they're walking through the crowded carnival, he tells them to hold his hand.
No.2 says he is jealous, then complains that Barbatos is a tough boss, and that Lord Diavolo is the only one who shows the Little D.'s kindness. Mammon points out that they still haven't found Diavolo and Lucifer, so No.2 takes them where he thinks the casino might be: a haunted house attraction.
Little D. No. 2 scares Mammon, and as he tries to let go of MC's hand, he realizes a curse has stuck their hands together. The group head deeper inside the building, where Mammon and MC get separated from No.2 and end up locked inside a room. An unknown voice asks the two questions about each other, and if they get them right, they can escape. If not, the will be eaten by zombies. The questions are about previous lessons, but even if the questions are answered correctly, the zombies are still set loose. Mammon and MC manage to escape, and find No.2 waiting for them.
Little D. No. 2 tries to get Mammon and MC to ride the roller coaster with him by claiming it must be the location of the illegal casino, but Mammon calls No.2 out for leading them on a wild goose chase. He suggests they ride the Ferris wheel, and when No.2 complains, tells him not to come with them. Once on the Ferris wheel, MC receives a text in the "House of Lamentation (New)(8)" group chat from Asmodeus, who wants to know where MC and Mammon are. MC replies they're at a carnival, to which the brothers say they're coming to find them.
MC and Mammon meet back up with No.2, and then Lucifer shows up with Diavolo. Seeing that Mammon and MC are holding hands, Lucifer notes that the zombie iguana MC is carrying is cursed. Lucifer demonstrates by asking for the plushie and touching Diavolo, who he becomes stuck to. He lifts the curse, then confronts Mammon about the illegal casino. Diavolo steps in to interrogate Mammon, dragging him away along with No.2.
Lucifer requests MC ride the Ferris wheel with him. While on the ride, he brings up how MC and Diavolo showed up at the meeting together that day. He states that since then, Diavolo hasn't seemed like himself, and MC convinces him that he should ask Diavolo directly. Afterward, Lucifer suggests looking for him and Mammon. If MC takes his offered hand, he speaks about a memory of holding Lilith's hand long ago.
They find Diavolo, No.2, and Mammon at a restaurant, where one of the ghost servers delivers a Babel parfait "the size of a mountain." Diavolo informs everyone that if the four of them eat it within an hour, they'll get it for free. Barely a third through the parfait, Beelzebub and Asmodeus arrive, and as Diavolo is explaining their hour is up, Beelzebub finishes the parfait.
Asmodeus informs Lucifer that all of their shopping is completed, and that Leviathan returned home to get started on the costumes. Diavolo and No.2 excuse themselves, paying the tab on the way out. Asmodeus complains that Lucifer and Mammon got to have fun while everyone else worked, and suggests doing something fun together. Beelzebub stays behind to take the Babel parfait challenge himself.
After riding a thrill ride called the heaven's wheel, Satan and Belphegor show up, who Asmodeus had invited. Satan wonders where Beelzebub is, then the group hears him throwing a hunger tantrum. Everyone heads back to the restaurant to find Beelzebub demanding another parfait after finishing the previous one in 15 minutes. When the ghost waiter declines, stating the restaurant will go bankrupt, Beelzebub transforms into his demon form.
Chaos breaks out as the ghost staff throws plates to fight back. Satan gets hit in the face by a plate of pancakes, and transforms into his own demon form in rage. Lucifer tells Satan to calm down, but this only makes him angrier. Asmodeus mistakes another plate thrown by a ghost as being thrown by Mammon, and hits Belphegor in the face with a cookie when trying to hit him. MC realizes they must do something, and invokes all six of their pacts at once, pinning the brothers in place.
Back at the House of Lamentation, the brothers are complaining about being sore from the command. Lucifer is silent even when Mammon snaps at Leviathan, who's arrived to show his preliminary costume designs. The topic of MC's power returns again at breakfast the next morning. Satan is amazed at how much power MC holds, and a sore Beelzebub complains that he was made to sit on his knees in MC's room as he was yelled at for two hours.
Asmodeus changes the subject to the upcoming dance as part of the school festival, and wonders who MC will go with. MC then shows up, with Lucifer arriving shortly after, bringing news that he's received a bill for the restaurant's damages. He states that everyone will be responsible for an even share of the costs. MC, Mammon, and Beelzebub all get jobs at Hell's Kitchen to earn money for their share.
Meanwhile, Simeon is having trouble writing the play's script. Solomon asks how Simeon went about writing TSL, to which Simeon replied he used the seven brothers as character models. This gives him a breakthrough, and he stays up all night finishing the script.
At the Demon Lord's Castle, Barbatos is subtly encouraging Diavolo to return to his work. Similar to when he showed doubt about his past actions at the colosseum with MC, Diavolo asks Barbatos if he always chooses the best course of action. Barbatos tells him his actions are always correct, but Diavolo doesn't appear fully convinced.
As director of the play, Simeon is strict on everyone and frustrated that his expectations aren't being met. Solomon shows up to talk to MC about using their pacts to subdue the brothers at the carnival. He comments that the first time he put multiple demons under control at once, his whole body was sore, and asks if MC is all right. Diavolo then arrives, and he and MC practice a love scene for the play. He also asks MC if they are feeling okay, and tells them that they can talk to him anytime.
Later, at the House of Lamentation, the brothers — minus Leviathan, who was working on costumes — are tired from rehearsing, and begin to argue. Lucifer attempts to stop them, but is ignored. Instead, they all stop talking to each other. MC visits Leviathan in his room, who says this happened a lot while MC was gone.
The brothers then start to use MC to relay their messages between each other, witch Simeon thinks is amusing when MC tells him and Luke about it at RAD. With the help of Lord Diavolo calling an emergency meeting, Simeon tells everyone that they're going to have another retreat at the Demon Lord's Castle.
At the castle, Simeon announces who will room with each other, and makes sure to group together the brothers that are fighting with each other the most. Diavolo and Barbatos will have their own rooms, and Solomon was busy, so he couldn't participate. Everyone will be rehearsing the play during the retreat as well.
When dinnertime arrives, Barbatos instructs everyone on how to make Babylon curry, but another argument breaks out, and ingredients start being thrown about the kitchen. At Barbatos's encouragement, MC uses their pacts once more to make the brothers stay, this time including Leviathan. Afterwards, Beelzebub is upset because he wasn't able to have any curry, so Belphegor gives him some pudding he found in the fridge, which leads to the two being able to make up.
The next day, Belphegor takes MC aside to let them know he knows that Luke made the pudding, and knows it was MC's idea. He then asks if MC would go to the school festival's dance with him. MC's choice here — as well as the choices they make later when each of the other brothers ask them to the dance — will have an effect on the story later.
Rehearsal then begins, and Satan gets into an argument with Asmodeus, who wants to switch places with him. It ends with Asmodeus storms off, and MC following after. While Asmodeus is trying to explain his side of things to MC, they hear a hissing sound, and find Satan trying to help an injured cat that isn't cooperating. Asmodeus uses his charming ability on the cat to calm it down, and then apologizes to Satan about their argument earlier. The two make up and return to rehearsal.
After rehearsal ends, Satan thanks MC for talking with Asmodeus. He then asks MC to the dance, and again MC can accept or refuse. A new argument breaks out between Lucifer and Mammon this time, but Simeon breaks it up and asks them to at least stay focused during rehearsals.
Later, Asmodeus tells MC that Lucifer has a soft spot for Mammon, but that Mammon has "always been the naughty type." He explains that when they were angels, Michael was in charge of training Mammon, but had difficulties with him, and asked for Lucifer's assistance. Whatever Lucifer did won Mammon over, and Mammon's training was turned over to him. Asmodeus assures MC that they will get over this fight eventually, and changes the subject by asking MC to the dance.
The end of the retreat arrives with at least most of the brothers having mended fences. Simeon — who has already been harsh throughout — warns everyone not to slack off, because he's going to continue being strict on everyone until the play is over.
Leviathan is upset that Beelzebub's costume won't fit because he's been eating too much. He asks MC to watch him to stop him eating while he fixes the costume. MC agrees, and while together, Beelzebub asks MC to the dance. Luke then happens by, carrying a cake he made, and Beelzebub goes into a rage, chasing him back to House of Lamentation. Both he and Luke collide with Lucifer, causing the cake to fly into Beel's mouth.
A furious Leviathan shows up, who changes into his demon form and summons Lotan. However, doing so floods the house and ruins all of the costumes Levi had been working on. With MC's encouragement, he decides to re-make just one costume: MC's. He succeeds with MC's help, and then asks them to the dance.
The next day at RAD, Lucifer explains what happened to Solomon and Diavolo, who find it all amusing. Barbatos arrives then, and whispers something in Diavolo's ear. Diavolo says he has to leave on urgent business, and Lucifer assumes he'll be coming along, but Diavolo instead takes Solomon with him.
In RAD's courtyard, Mammon comments that Lucifer is trying to hide how upset he is, then insists that MC has something they need to ask him. MC can choose to ask him to the school dance or not. Either way, Mammon lets MC know that Lucifer tends to retreat to the music room and listen to classical music when he's upset, and suggests they visit him tonight.
MC does so, and Lucifer tells MC that he heard from Diavolo that he'll be unable to make it to the play tomorrow, so Simeon cut out his scenes. MC and Lucifer practice the play together, and MC can try to ask Lucifer to the dance or not. If they do, Lucifer interrupts and tells them to get a good night's sleep.
The play — titled "With Me" — begins the next day, and the choices MC made in Lesson 25 are reflected in how the story plays out. In the middle of the play, Lucifer changes his character's dialogue so that he can ask MC to the dance. The play continues, and MC's character is given a dagger so that they can kill the princess and marry Lucifer's character. They are unable to bring themself to do so, but Lucifer's character vows to renounce his royal birthright to be with them.
Once the plays is over, Little D. No. 2 shows up, and tells MC that Simeon wants to meet with them in the courtyard. MC goes there, and Simeon thanks them for their help in getting the brothers to do their best for the play. He then suggests that MC could either come with him to the Celestial Realm once their studies are finished, or he could come with them to the Human World.
MC heads back inside to find Diavolo and Solomon having just returned, and Diavolo asks who MC chose to go to the dance with. If only one of the brothers was chosen, they show up and take MC to the dance hall. If MC chose more than one, most of the brothers are upset by this — although Asmodeus, Beelzebub, and Lucifer seem more understanding — and MC ends up dancing with everyone. If MC chose none of the brothers, they end up going with Solomon.
After the dance is over, Lucifer finds Diavolo at the colosseum and asks him what has been going on. Diavolo replies that it isn't the right time to tell him yet. Lucifer also asks about the day he and MC were together when Leviathan's 3D escape game activated. Diavolo tells him that he, his brothers, and MC share a special bond, and that makes him jealous. Upset, Lucifer asks if he's suggesting that they don't share a bond with him as well, and Diavolo admits they do, but can't help feeling anxious. Lucifer tells him no matter what, he'll be by his side, and the two leave for the cast party.
The brothers are hanging out in MC's room, relived that the play is over, until Leviathan mentions that exams are coming up. Mammon, Beelzebub, and Leviathan complain about how difficult exams are, and Mammon tells MC they're lucky they're an exchange student, so their scores don't have to be as high.
MC encounters Lucifer in the hall, and he tells them he was able to speak with Diavolo about his recent odd behavior, then asks if MC is doing alright. He suggests they talk to Solomon about using the magic of pacts. MC meets with Solomon at RAD, and he shows them the Ring of Wisdom that was given to him by Michael. Wearing the ring gives him the power to control demons, but when he was still new to having pacts, the energy needed to use them made him incredibly sore. He finds it odd that's not the case for MC, but they're interrupted by a text on MC's D.D.D..
The text is about an emergency meeting that MC also attends, where Diavolo announces that for the upcoming exams, MC will be given the same pass/fail standards as the regular students. Mammon and Belphegor argue that's too much for MC to handle, but Lucifer tells Satan that he will be tutoring MC for the exams.
Tutoring with Satan begins with seductive speechcraft, and Leviathan joins due to his poor scores last exam. Satan explains the steps to seducing a human are to "look at them with a kind, friendly smile" and to "tell them that I'm a demon." Satan then tells Leviathan to seduce MC, but when he tries, tells him he did a poor job, and gives his example of seducing MC. Then it's MC's turn to seduce Satan, who passes if they choose to meow at him. Afterwards, in Leviathan's room, MC helps him practice by pretending they're in a dating sim, and he asks MC to stay the night so practice can continue.
The next lesson focuses on curses and hexes, this time with Mammon joining. They start with the basics, like explaining the word for "curse" in Latin is "Imprecatio." Then Satan asks MC to try cursing Mammon. MC messes up, instead causing Mammon to be overcome by desire for them, so Satan kicks him into unconsciousness. He then tells MC that performing curses takes a toll on the body, and uses a spell to fix MC's dizziness. MC uses the same spell on Mammon later to take care of his soreness.
Out in the Devildom, MC comes across Luke and Simeon, who suggest that they should all study together, though Simeon has to cancel later. This time, the focus is on magical potions with Beelzebub joining, and they're in the twins' room instead of the library. Satan again starts with the basics, like how the elixir of cerebral stimulation requires powdered unicorn hoof, bittergrass root, and caladruis blood as ingredients.
When making the potion, Belphegor has to stop Beelzebub from eating the ingredients. In the middle of brewing, however, he still drinks MC's potion. The unfinished potion makes him behave like a cat, and MC keeps him occupied while Satan researches a cure. After he's cured, Mammon suggests giving the potion to Lucifer. MC makes another potion, but Leviathan makes Mammon drink it instead. Because he didn't drink all of it, he's still able to talk, but also meows like a cat.
Lessons with Satan continue, this time with Devildom history. Both Luke and Simeon are able to join this time, while Solomon is at the Demon Lord's Castle again. Asmodeus was also meant to join, but he skipped tutoring to go shopping with Mammon.
Satan explains that the Devildom came into existence at the same time as the Celestial Realm, and then covers some basic trivia, such as shortly after the Devildom came into existence, its surface was covered in a forest. There is also a relief sculpture at the entrance to the Devildom royal tomb that depicts a three-legged crow.
At some point during Satan covering the Great Celestial War and the aftermath, both Luke and MC fall asleep. Simeon comments that he thinks its amazing that after such a violent history, angles and demons can now study together in peace.
Later in Asmodeus's room, Asmodeus complains to MC about the work Satan gave him for skipping his tutoring session. Then the next day, exams begin at RAD. Day 1 covers magical potions and Devildom history. Belphegor falls asleep mid-exam, but only because he finished early. Before leaving, he invites MC to hang out in the planetarium that night. On their way back to the House of Lamentation, MC crosses paths with Solomon, who is again on his way to the Demon Lord's Castle.
After the first days of exams, Mammon, Leviathan, Asmodeus, and Beelzebub are at The Fall when Asmodeus mentions that tomorrow's exam is seductive speechcraft. The idea of practicing with MC before the exam encourages each of them to head home. Meanwhile, MC meets with Belphegor in the planetarium, who tells them about the twin stars that appeared in the sky after the Great Celestial War ended, and how they represent him and Beelzebub.
The exams on day 2 are curses and hexes and seductive speechcraft, and in both, MC must choose one of the brothers as a partner. Once exams are over, there is another student council meeting that MC also attends. If MC was able to answer at least four of the exam questions correctly, their exam score is excellent and Diavolo praises them for how well they did. If they answered at least two questions correctly, they passed with average exam results. If fewer than two were correct, Diavolo says they were only barely able to pass, but Mammon, Leviathan, and Beelzebub reassure MC that it's okay and they did well enough.
Mammon announces that it's time to party now that exams are over, and everyone heads to The Fall except Lucifer, Diavolo, and Barbatos. Barbatos brings Lucifer some tea, and Lucifer asks him if he can tell him anything about Diavolo's recent behavior. Barbatos refuses, then warns Lucifer to be prepared in case he'd ever face the decision of staying by Diavolo's side even if it meant hurting those closest to him.
After partying, everyone makes it back home where MC hears music playing, and finds Lucifer in the music room. He tells MC that he feels like something bad is happening, but Diavolo won't tell him yet what's going on. He then brings up the play from earlier, and asks what MC would do when faced with the choice of duty or love, but then tells them to forget what he said.
At some point after the botched potion that MC made caused both Beelzebub and Mammon to have cat-like behaviors, Mammon tasks MC with giving the potion to Lucifer. MC goes to Lucifer's room and gives him a drink laced with the potion, but nothing happens. He tells MC that he's able to resist the effects of most potions and elixirs, then asks MC if they'd rather be punished by spending the night with him, by pretending to be a cat, or by meowing as cutely as they can.
Mammon, Leviathan, and MC are playing video games in MC's room — with Beelzebub cheering them on while snacking — when Leviathan mentions a time loop game called "The House of Sorrow" is releasing next week. The game's murder mystery story is based on events that happened in the House of Lamentation back when it was still in the Human World. Suddenly, Asmodeus bursts into the room to announce there will be a bloody moon this weekend.
In the dining room, the brothers explain that a bloody moon is a night when the Devildom moon turns red. During the bloody moon, the bloody moon competition is held, when students at RAD vote to decide who the most honored and respected demons are. Everyone expects Diavolo and Lucifer to take first and second place, as they always do, but Asmodeus seems upset about something. He invites MC to his room, where he tells them he wants to come in first for this year's competition, and asks for MC's help to do so.
Asmodeus also asks for help from Satan and Belphegor, as they're members of the "Anti-Lucifer League." The two agree, and suggest plans to sabotage Lucifer's reputation, but in the end the plan is to improve Asmodeus's image. They decide to make a promo video for him to upload on DevilTube, and Satan asks Mammon to help direct it due to his experience as a model.
They set up to film in Asmodeus's room, because Mammon wants to focus on letting people see the "real Asmodeus." When the video is uploaded, it does as well as all of Asmodeus's other video, but no better. Next, Satan suggests throwing a fundraiser party at Ristorante Six. Asmodeus struggles with taking Mammon's advice from earlier, but just sounds awkward. Meanwhile, they find out from a chat Beelzebub sends that Lucifer is at Hell's Kitchen and is paying for everyone in the restaurant.
The next day, Satan reveals that the RAD Newspaper Club released an article about Lucifer treating everyone at Hell's Kitchen, which upsets Asmodeus, so MC goes to Solomon to asks for advice in cheering him up. He suggests shopping, which MC and Asmodeus do. This does cheer Asmodeus up, until a text from the RAD Newspaper Club announces that Diavolo has dropped out of the competition, and is backing Lucifer instead.
After returning to the House of Lamentation, MC talks to Lucifer in his study about the news. He tells MC that he still doesn't know what Diavolo is doing, and didn't know he was dropping out until asked for an interview. He also explain that he paid for everyone at Hell's Kitchen earlier because it was the owner's birthday, and doesn't really care about the bloody moon competition.
Asmodeus still refuses to give up, but after a tense breakfast, another text from the RAD Newspaper Club announces that after Lucifer, Beelzebub is in second place, with Asmodeus in third.
Meanwhile, Simeon brought some cake sent to him by Michael to the Demon Lord's Castle for Diavolo to try, though his meeting is something he's keeping a secret from Luke. He brings up the secrets Diavolo and Solomon are keeping, and delivers a message from Michael that if these secrets affect the Celestial Realm, then the angels will intervene.
MC and Belphegor are playing Old Maid in the twins' room while discussing the current results of the bloody moon competition, and why Beelzebub just being himself is why he's currently in second place. MC then heads into the hallway and finds Asmodeus trying to get into Leviathan's room. MC says the password needed, and Asmodeus asks Leviathan to sew ten outfits that he designed. Asmodeus wants to throw a party tomorrow with a fashion show, and after saying he and MC will help, Leviathan begrudgingly agrees.
The next morning, Mammon find Leviathan, Asmodeus, and MC asleep on the floor in Leviathan's room, but Lucifer tells him to let them sleep. The party begins that night, with many famous people invited. Asmodeus announces the theme of today's show is "Keeping It Real," and that the outfits in the fashion show represent true "Asmo styles."
Solomon compliments MC for making Asmodeus feel better, and when Luke says that he won't be voting for any demon in the competition, Simeon points out that only demons are allowed to vote anyway. Solomon then gets a call from Barbatos, and suddenly has to leave. Lucifer then appears, and when Simeon asks about a meeting, explains that Diavolo had to cancel as something came up last minute. Asmodeus notices him there, and scolds him for trying to keep MC to himself before pulling MC away with him.
The two take to the dance floor, where Asmodeus tells MC that he's in a great mood, and it's all thanks to MC for helping him realize how to be true to himself. However, the next day at RAD, all he can do is worry about the votes. The voting takes place, and the results leave Asmodeus and Lucifer tied for first with only one vote left...Lucifer's. Asmodeus is certain he's lost, but Lucifer votes for Asmodeus, and Diavolo announces him the winner.
At the House of Lamentation, Asmodeus can't stop crying and telling Lucifer how much he loves him. At first he'd been upset, because he thought Lucifer voted for him out of pity. Instead, Lucifer explained that his talent for fashion design and being able to charm almost everyone he meets makes Lucifer respect him for his abilities. Belphegor then notices that Leviathan is missing, and Satan says he hasn't seen him all day.
MC and Asmodeus head to Leviathan's room to try and find him. On the way, Asmodeus thanks MC again for helping him with the competition, and says he now better understands both himself and Lucifer. They then knock on Leviathan's door, but suddenly hear him scream. The two rush into his room to find him unharmed, but upset about something, and saying Lucifer's going to kill him.
Out in the primeval forest in the Devildom, Diavolo, Barbatos, and Solomon examine an entire cliff that has collapsed. Barbatos also mentions that a few days ago, there was an incident at Demon King's tomb. Solomon suggests letting Simeon and the Celestial Realm know about this. Diavolo states that he has difficulty dealing with Simeon, and asks Solomon to speak to him in his stead.
When Barbatos asks about what to do with Lucifer and his brothers, Diavolo tells him that they should keep this from them a little longer, despite knowing it's a bad thing to do. He wants to have proof that MC is the source of what's happening before telling them anything.
In the library, Lucifer demands to know what Leviathan has done, and he admits the time loop game "The House of Sorrow" had a charm cast on it by developers to keep people from playing it before the official release. Because he loaded up the game early, a message appeared saying the current day will repeat endlessly until whatever someone was wishing for the moment the charm took effect comes true. Everyone's memories will also be reset each day.
Lucifer tasks Leviathan with making everyone's wish come true, and both he and MC retreat to MC's room to decide who to start with. Leviathan refuses to start with himself, and suggests starting with Lucifer instead. Lucifer says that he learned Mammon was a bookie for a group of RAD students during the bloody moon competition and made money doing so. He wished that Mammon could become a proper demon, and when asked what that means, he says a "proper" demon is honest and doesn't make things difficult.
Leviathan produces a bangle that forces wearers to tell the truth, and can only be taken off by the person who put it on. He'd gotten it from Satan, who planned to use it to prank Lucifer. He puts the bangle on Mammon, who admits that he likes and respects Lucifer, but doing so doesn't break the time loop.
Next they try to grant Mammon's wish, and when he refuses to admit what it is, the bangle is put back on him. He again tells the truth, and says that he wanted MC to only be sweet and happy when alone with him. Leviathan runs off, leaving Mammon wearing the bangle, and because he can't stop admitting truths out loud, hides with MC in the bathroom.
He tells MC that he likes them, and his wish is to hear them say they like him too. MC does say they like him — though how they mean it depends on the player's choice — but suddenly Leviathan appears from the bathtub, because he was hiding there when Mammon and MC came in.
Upset that Mammon's wish didn't break the time loop, Leviathan next moves to granting Satan's wish. He and MC find him in the living room, and he says that his wish was to see Lucifer kneel at his feet. Leviathan thinks the best way to get that to happen is by accident. He gets Lucifer into the room, and MC drops a magazine at Satan's feet. Asmodeus picks it up, ruining that plan, so Leviathan tells Lucifer his shoe is untied. Not knowing who he's talking to, both Lucifer and Satan bend down, knocking their heads together.
Leviathan then admits what Satan's wish it to Lucifer, who doesn't even hesitate to kneel before Satan, telling him it's sweet that's all that it takes to make him happy. Satan doesn't seem happy with this, but his wish was still granted, and the time loop remains.
Meanwhile, at Purgatory Hall, Luke brings Simeon some tea and cake, who is working on writing a spin-off to The Tale of the Seven Lords. Despite the recipe being new, Simeon gets the feeling he's had this cake before. Solomon then appears with some food that he's made, and when Simeon suggests letting everyone at the House of Lamentation try it instead, he tells them about Leviathan triggering a time loop.
Asmodeus's wish is next to be granted, and his wish is that he wants to charm MC as a reward for helping him win the bloody moon competition. Asmodeus's charming ability doesn't work on MC, but he, MC, and Leviathan go to his room to try anyway. When it still doesn't work, he gets sidetracked and pulls out a photo album from when he was an angel.
When looking at the pictures, Asmodeus claims that MC is emitting an aroma of attraction. This makes him feel like he was able to charm them just a little, but that's another wish granted without fixing the time loop. Leviathan and MC move on to Beelzebub, whose wish is to drink a "siren's song." To prepare the cocktail, you have to listen to a siren's song, which makes the listener lose their mind and want to jump in the nearest body of water to drown. Leviathan suggest using a record Lucifer has of a siren's song, and they all go to the music room to find it.
Meanwhile, Lucifer visits the Demon Lord's Castle because Diavolo invited him for tea. Barbatos greets him, and is amused about hearing their issues in dealing with the time loop. Diavolo is happy that Lucifer still meets with him despite having other things to deal with, but when he jokes it wouldn't be so bad to repeat this day, Barbatos reminds him of the stack of paperwork he still needs to sign after tea is over.
Leviathan and Beelzebub look through Lucifer's records, but don't let MC help in case they touch one of the many cursed records. The records is found, and Leviathan makes the drink wearing earplugs while Beelzebub and MC cover their ears. Beelzebub then drinks the cocktail, and the time loop still isn't fixed.
Leviathan and MC find Belphegor in his room, who says his wish is to nape with MC. He then orders Leviathan out, and MC sits on the bed while he rests his head in their lap. He isn't tired, however, so asks MC to sing him a lullaby. MC sings the siren's song, and Belphegor tells them that a long time ago he, Beelzebub, and Lilith listened to that song once.
Belphegor eventually falls asleep, and Leviathan returns to check on them. With another wish granted, only Leviathan's wish remains. He finally admits that his wish is to play games all night alone with MC. They do so, and after falling asleep, wake up to find that the charm is gone.
At breakfast, Lucifer is exhausted, and wishes for a break from the constant mayhem being caused. Mammon then shows up and tries putting the charmed bangle on Lucifer, and Satan succeeds after he fails. Lucifer promptly breaks the bangle, but before he can deal out punishments, Beelzebub enters the room and tells Lucifer they have a problem.
In the music room, Beelzebub explains that he wanted to have one more siren's song, and tried making the cocktail himself. However, the earplugs he was wearing fell out, and under the song of the siren's spell, he thrashed around until he bumped the needle of the record, stopping the music. The record player is still turned on, and now with everyone in the room, the record starts playing again. Everyone races to the bathroom in search of water, nearly trampling a visiting Solomon, who fortunately performs a spell to end the curse. Unfortunately, he was visiting because he brought food he made for everyone to try.
Before anyone has to eat the food, Lucifer arrives with one of his records broken in half. The record, the "Hymn of the Reaper," is a song from an opera of the same name, sung by the reaper as they extinguish the candle representing the soul of the protagonist. Everyone worries that because Beelzebub broke the record, he's incurred the wrath of the reaper, who now might extinguish his soul at any moment.
Satan explains to MC that housed within a Reaper's Cave are the Life Candles representing the souls of humans, demons, and angels. Belphegor suggests going to the cave to check Beelzebub's candle, but Satan points out that no one know where it is. Except Solomon does know, and they all head outside so he can draw the magic circle needed to get there.
Solomon warns that the reaper is likely to accuse them of trespassing, but doesn't give anyone time to think on that before saying the spell to transport them to the cave. Once everyone lands, Leviathan find a message written in blood directed at Solomon. The message states that if he tries "sneaking inside" while the reaper is gone, they will destroy his life candle. When Leviathan asks Solomon what he did to make the reaper so angry, he replies that he can't think of anything.
Mammon suggests that the reaper not being present is a good thing, as now they can check Beelzebub's candle and leave without being noticed. Before they enter the cave, Solomon tells everyone that there are rules that must be followed. Each level of the cave has a different rule, and if broken, there will be a terrible punishment.
Hearing this, Beelzebub wants to go alone, then when everyone insists on going with, argues that MC is particularly endangered, as they're a human. Asmodeus argues that MC is no ordinary human, as they are powerful enough to use their pacts with the seven brothers as needed.
The first level of the cave looks like an open field, and the rule for this level is "Don't look back." To trick them into breaking the rule, everyone hears different voices behind them, calling them to look back. Leviathan, hearing the voice of Ruri-chan, looks back, and is turned into a Little D..
Level 2 of the cave looks like a library, and the rule is "Do not touch." Beelzebub notices a mark on Mammon's wrist that looks like Midas's Crest, the bearer of which can turn whatever they touch into gold. It's not really the crest, but Mammon still attempts to touch things, and is turned into a Little D. as well. Satan meets the same fate immediately after, as he was tricked into trying to pick up what he thought was a kitten meowing at him.
Solomon comments that he'd assumed something more terrible would happen to those who broke the reaper's rules, and wonders if something is protecting the brothers. Mammon then asks Solomon if he'll give him a real Midas Crest. After Mammon refuses Solomon request for a pact in return, he agrees instead to help Solomon forge a pact with Lucifer. He changes his mind, however, when Asmodeus points out that with the crest, he wouldn't be able to touch MC anymore.
Asmodeus is curious about the reaper, and asks Solomon what they're like. He replies that even though they've known each other for over a thousand years, there's much Solomon still doesn't know about them. MC is shocked that Solomon is so old, so he explains that long ago, he was researching new forms of magic, but made a mistake that led to him being unable to grow old or die. Lucifer calls for everyone to keep moving, but MC thinks they see Solomon take a book off one of the shelves as they head out.
Level 3 of the Reaper's Cave has the rule "No talking," and because their D.D.D.'s don't work in the cave, texting also isn't an option. Everyone tries communicating with each other by thoughts, which doesn't work well for any of the brothers besides the twins. They all still manage to understand MC, however. Satan, Mammon, and Leviathan are able to speak aloud because they're already Little D.'s. Asmodeus opens a door into a closet full of designer clothes that he can't help but start talking about, and is turned into a Little D. as well.
Level 4 of the cave is a series of rooms filled with food, and the rule is "Do not eat." Beelzebub is able to resist the temptation until Solomon spots a dish just like one MC made during their retreat at the Demon Lord's Castle. To save his brother, Belphegor eats the dish instead. Solomon notices Lucifer look pale, and he replies that his head hurts.
They reach Level 5 of the cave, which has no rules, and Belphegor finds the Life Candles representing the seven brothers, with MC's candle right next to them. Beelzebub's candle, however, is nearly burned down and is burning much faster than the others. He asks if there's a way to summon the reaper so he can explain and apologize, but instead, Lucifer pours some of the essence of life from his candle into Beelzebub's. Each of the other brothers follow suit, even though this will shorten their own lifespans.
This buys Beelzebub some time, but his candle is still burning too fast. MC then pours a single drop of their candle's essence into Beelzebub's, and in a burst of light, his candle returns to normal again. Solomon transports everyone back to the House of Lamentation, and Lucifer heads inside to rest in hopes of treating his headache.
MC is able to ask Solomon several questions. When asked about the stolen book, Solomon explains he and the reaper have competitions sometimes. As he won the last one, he's allowed to take one item as a prize, which is why he wasn't punished for breaking the "Do not touch" rule. Solomon also explains that he once invited the reaper to eat some of his cooking, and they've disliked him ever since "for some reason." When asked about his age, Solomon admits he no longer remembers how old he is.
Once back in the house, Asmodeus asks Solomon to change everyone turned into a Little D. back to normal, which he does, and Beelzebub then takes MC aside to thank them for what they did in the cave. Solomon interrupts them, however, and tells them that Diavolo has been keeping secrets from them. He doesn't agree with that decision, and starts to tell them something, only for everyone to hear Lucifer scream. They all rush to the dining hall to find Lucifer collapsed on the floor.
Meanwhile, Diavolo, and Barbatos, and Simeon examine a hole in the forest that has grown larger in the past days, and Diavolo tells Simeon that the Royal Tomb has collapsed as well. Nothing like this has happened before, and it's Solomon's opinion that MC is the cause.
Simeon asks why Diavolo's kept it a secret from the brothers, and why Lucifer in particular is so important to him. Diavolo gives a vague non-answer, and Simeon tells him that he should have told Lucifer about these happenings right away. Barbatos agrees, and Diavolo decides to send Lucifer a message to come see him so that he can tell him everything.
An unconscious Lucifer is carried to his room, where Belphegor brings up that he kept mentioning his head hurt while in the Reaper's Cave. Solomon had left to fetch Diavolo, and returns with him as well as Barbatos, Luke, and Simeon. Diavolo is distraught over seeing Lucifer, and exclaims that this is all his fault. He asks for MC's help, and everyone but Luke — who is keeping an eye on Lucifer — heads into the living room.
Diavolo explains that unprecedented phenomena have been taking place in the Devildom, such as the Royal Tomb collapsing and holes opening in the forest. Solomon admits this is why he brought MC to the Devildom, and that similar phenomena have also been happening in the Human World. Simeon adds that this is happening in the Celestial Realm as well, though at a lesser extent. Diavolo then bluntly states that he and Solomon believe MC is the cause. Luke then runs in to let them know Lucifer is awake.
Initially, everyone is relieved that Lucifer is awake again, but when Lucifer asks who they are, they realize that he has amnesia. Barbatos puts Lucifer back to sleep, and Luke again stays to watch him while the rest return to the living room. Diavolo continues his explanation, and tells MC that being a human, the distant descendant of an angel, and having pacts with all seven of the brothers, means that MC shares deep bonds with all three worlds. After hearing Solomon's theory about these bonds, Diavolo subjected MC to exams at a higher standard to test their powers.
The test results didn't show MC to be capable of powerful magic on the surface. Because MC cannot fully control the power granted by the "ring" their connection to the three worlds creates, MC's powers has caused a negative impact on all three worlds without realizing it. Diavolo states there are two possible ways to fix this: MC gains the ability to control their powers, or the "ring" is severed.
The only magic item that could help MC control their powers is the Ring of Light. This ring once belonged to Lucifer, but he lost it during the Great Celestial War. Severing the "ring" would require the power of the Night Dagger Solomon took from the Reaper's Cave. Using it would mean MC's pacts with the brothers would also be severed, and as Diavolo tells Mammon, once a demon's pact is broken, it's permanent. However, severing the ring might also return Lucifer's memory.
After announcing that Solomon will perform the ceremony needed to sever the ring, Diavolo apologizes to MC and hugs them. Solomon needs to do research first, and leaves along with Diavolo, Barbatos, and Simeon. Before Luke leaves also, he tells MC that Lucifer was saying their name in his sleep.
Back in Lucifer's room, Asmodeus is showing Lucifer a photo album from when they were in the Celestial Realm, but it only has pictures of himself. After Lucifer complains, he leaves to get different pictures, but reassures MC before he goes that even without a pact, their relationship will still be the same.
Lucifer tells MC he now knows what Asmodeus is like, but asks about his other brothers. MC has the choice to provide a more positive or negative opinion on each of them. He then asks about his relationship with MC, with options given to be romantic or not. Beelzebub then brings Lucifer some food, and tells him about how he gave some of his Life Candle's essence to him. He then gives both Lucifer and MC a hug.
Then next day, MC finds Lucifer in the attic with Belphegor sleeping with his head on Lucifer's lap. MC joins them, and the three nap together. Later, Mammon is talking to MC, and the two find Lucifer in front of Leviathan's door. MC provides the correct secret phrase about the second lord "having incurred the wrath of the Lord of Corruption."
Lucifer wants to play video games, so the four of them play "Super Smash Devils" together, with Lucifer insisting that he won't quit until he manages to beat Leviathan. Leviathan takes a moment to tell MC that even without a pact, the two of them will still get together and game.
While all of this is happening, Little D. No. 2 finds Barbatos to tell him Diavolo is acting strange. Barbatos find him and asks him what's wrong, and Diavolo replies that he want to check on Lucifer, but doesn't feel he has the right. Barbatos disagrees, but advises to trust Lucifer's brothers and MC to look after him.
Satan tries to convince Lucifer not to play cards with Mammon because he's worried Mammon's trying to take advantage of him having amnesia. Lucifer won't be convinced, so Satan asks MC to go with him. The two join Mammon in his room, and Mammon suggests playing "The Witch and the Black Cat," a card game where two players try to take each other's face cards. If Mammon wins, he gets to use Lucifer's credit card for one day. If Lucifer wins, he gets MC to himself for one day, though he tells MC he'd ask for something else if they didn't like the idea.
The card game begins, but Lucifer is distracted by regaining memories of Mammon's Demonio 666 Lexura. The color for the car Mammon wanted was limited edition, so Lucifer secretly asked Diavolo to help him get it for Mammon. He then told Mammon that he found a dealer who had the car in stock.
The game ends with Lucifer winning, who then leaves MC with Mammon. Mammon tells MC that even if their pact is severed, he's still their first demon. Later in the library, he tells Leviathan and Satan that Lucifer will have MC to himself tomorrow. The three start making plans to intervene, but Lucifer shows up and thanks them for helping him while his memories are gone. This makes them change their minds about interfering with him spending time alone with MC.
The next day, Lucifer and MC are on their way out of the house when they run into Solomon. He says he wanted to talk to MC, but he'll just come back tonight. He also suggests they go to Devil's Coast, as it's the last day they're open. They take Solomon's advice, and end up riding the ferris wheel just as they'd done the last time. Lucifer tells MC that even without his memories, MC is special to him.
After the two return to the House of Lamentation, MC finds Solomon waiting for them in their room. He tells them he researched the Night Dagger only to find its magic power has waned over the years, and so would not be strong enough to sever the ring of MC's powers. The only way to restore the dagger's power is to kill a demon with it and have the dagger absorb said demon's power.
Solomon hands MC the Night Dagger, and tells them to use is on Lucifer, but then says he's just kidding. He says that he has always put the interests of the Human World above all else, but he doesn't want MC to hate him. Lucifer then enters the room, who overheard everything.
Lucifer tells Solomon to leave, then holds onto MC's hand and tries to get them to use the dagger on him. However, Simeon appears and puts the Ring of Light on MC's finger. MC sees a blinding light, and a disembodied voice speaks to them, saying they're jealous of MC, and that they loved Lucifer and his brothers, but lost them. They then tell MC the Ring of Light will protect them now, and returns MC to their room.
At the Demon Lord's Castle, MC, Luke, Simeon, and Solomon all talk about recent events. Now that MC has the Ring of Light, the chaotic ring of MC's connection to the three worlds has stabilized. Lucifer's memories have also returned, when then unleashed his anger on both Solomon and Diavolo.
Solomon asks MC — who now ranks as a sorcerer with powers as strong as his — if they'd help him protect the Human World by helping him decide what to do in future complicated situations. MC agrees, then Solomon asks Simeon how he was able to find the Ring of Light. Simeon explains that he suspected Michael had the ring, so went to the Celestial Realm to "borrow" it from him. Barbatos then arrives to tell them "the preparations are complete."
Meanwhile, Diavolo attempts to explain to an angry Lucifer why he'd kept secret that MC might be the cause of the destructive phenomena. Solomon comments that this is why he advised Diavolo to tell Lucifer, but Simeon points out that he also didn't tell Lucifer, and that he tried to convince MC to stab him with the Night Dagger.
Diavolo comments that Lucifer sounds more rough now than he did before, and that Lucifer should always talk to him in this more "real" way. Lucifer isn't happy about that, so Diavolo says that he got him a painting from the famous unknown Devildom artist John Smith. While still angry, Lucifer is also moved that the painting he'd wanted is now his. As Solomon tries to make his exit, Lucifer's ire moves on to him.
At the Demon Lord's Castle, Diavolo tells MC how surprised he was when Simeon told him that they'd received the Ring of Light's blessing. MC then remembers waking up just after being given the Ring of Light to the brothers bursting into their room, worried because Beelzebub said that he saw Celestial Realm light coming from there. Lucifer warns them to be quiet if they don't want a repeat of what happened at the carnival when MC told them all to "stay." Everyone realizes this means that Lucifer's memory has returned, and an exhausted MC falls asleep.
Back in the present, Diavolo thanks MC for saving both Lucifer and the Devildom, and tells them there's a party in their honor today. Everyone is in their demon forms for the event. Leviathan mentions he's surprised that Lucifer still remembers what happened while he had amnesia. Satan and Belphegor both say that they preferred Lucifer when he had amnesia, but Asmodeus calls them out on actually being relived that Lucifer's back to normal.
Diavolo then asks MC to dance with him. He tells them that as the living embodiment of bonds between the three world, MC is a very important person, and he feels that he can place his trust in MC. He wants to say more, but the song ends, and Luke asks to dance with MC next.
The next morning at the House of Lamentation, Lucifer is mostly the same as before, but now seems even closer to his brothers. Out in the Devildom, MC runs into Luke, Simeon, and Solomon, who reminds everyone that they'll be returning home soon. MC brings this up to the brothers when at RAD, and Asmodeus suggests asking Diavolo if MC can stay longer. When MC does this, Diavolo points out they have a life in the Human World to consider. Afterwards, Belphegor suggests asking Solomon to teach MC how to teleport between the Devildom and Human World.
Solomon tells MC they have the raw power to learn teleportation, but lack the skills, so MC will have to start with the basics first. He asks MC to become his pupil and learn magic from him, though he points out learning to teleport could take years. Instead, he suggests learning to use their pacts with the brothers to summon them to where they are.
He explains further that if the brothers each give MC "something that is dear to them," their gifts will act as permits that would allow MC to summon them across worlds anytime. MC returns to the House of Lamentation, then they hear a loud noise. They find Satan in his room beneath a collapsed pile of books. He blames Lucifer for this, because he'd asked Satan to tidy his room.
MC helps him clean, and explains what they learned from Solomon. Satan then gives them the Forbidden Book that causes people to switch bodies when two people touch it at once. The magic has faded, so it no longer has that power, but it's connected to an important experience to Satan, so he wants MC to have it.
At the house's entrance, MC finds Asmodeus lugging boxes filled with clothes he hasn't worn recently. Lucifer ordered him to get rid of what he doesn't need. MC starts to ask him about getting a gift from him, but Asmodeus beats them to it, having already heard what was going on from Solomon. He doesn't know what to give MC, but the two decide to take pictures together, and both save a copy to their D.D.D.'s.
Next, MC finds Belphegor trying to hide because Lucifer told him to clean the attic, and they ask him for a pact gift. He gives them his star, one of the two twin stars in the Devildom sky that represent himself and Beelzebub. He then says next time they'll look at the stars together in the Human World.
Later, Diavolo comes to the House of Lamentation to visit MC, and tells them "a friend of his" has been acting cold towards him because he was keeping secrets from said friend. He asks MC for advice, then Barbatos tell him that his tea is ready. He also comments on MC doing a good job advising Diavolo. Lucifer then asks Diavolo to at least seek MC's advice about him when he's not in the same room.
Leviathan brings a box of games and DVDs to MC's room because Lucifer asked him to declutter his room, so he wants MC to take them back to the Human World. Then, for his pact gift, he presents the script to "With Me," the play they performed for the RAD school festival. He tells MC they have to summon him whenever there's any event he wants to go to, then gives MC a hug, and tells him they'll still game online together every night.
MC then finds Beelzebub in the kitchen, because Lucifer told him that he could eat anything but the emergency rations. He knows about the pact gifts, and that Belphegor gave MC his star, so he wants to also give MC his star. He also says he was once leader of Lucifer's personal guard when they were in the Celestial Realm, so if MC gets into trouble in the Human World, they should call him.
MC next finds Mammon in his room trying to avoid Lucifer, who told to repay any debts he has in the Devildom right away. He too knows about the pact gifts already, and gives MC one of the "Harrison Porter" keychains they bought when they went to the Human World together before. He then tells MC that when they summon him to the Human World, he'll refuse to leave and stay by their side.
Later, MC hears music coming from Lucifer's secret study. They find Lucifer there, and he shows MC the Gold Hellfire Newt Syrup he has, telling them he mixed it with the Demonus he's drinking. MC gives him an order to either kiss them, or give them something precious to him. Either way, for his pact gift, he tells MC they already have it: the Ring of Light. He's happy that something once belonging to him now keeps MC safe.
The next day, MC visits Purgatory Hall for some tea, and Solomon tells them once they return to the Human World, he'll teach them the magic needed to summon the brothers. MC then visits the Demon Lord's Castle with Luke, who's going to see Barbatos about a new recipe. Luke and MC are greeted by Barbatos at the castle, then Diavolo appears and asks to talk to MC. They go to the garden, where Diavolo admits that he doesn't want to send MC back to the Human World. He again is interrupted in trying to tell MC something when Luke shows up with some muffins he made.
On MC's last day in the Devildom, everyone throws MC a surprise party. Diavolo teleports them all to The Fall, where he'll be paying everyone's tab. When taking a break from the party, Simeon tells MC that he, Luke, and Solomon decided to leave today instead of tomorrow. He explains that Michael wants a report on what's happened during the crisis caused by MC's powers. Solomon also says he wants to see the situation in the Human World for himself.
Luke openly admits he'll miss the Devildom, and that thanks to MC, he realizes that he needs to make some changes in himself, and that it's not right to condemn someone just for being a demon. The brothers then find MC and bring them back to the party.
Early the next morning, MC wakes up inside a sack being "kidnapped" by the brothers, minus Lucifer. The sack is opened when everyone is inside the underground tomb, where an emergency escape route leads to the far reaches of the Devildom. Everyone is nearly attacked by Cerberus, who is guarding the tomb, but Lucifer appears and tells him to sit. He then gives them instructions for how to find the escape route, but as soon as they make it to the outskirts, they're met by Diavolo and Barbatos.
Diavolo wasn't surprised the brothers pulled this stunt, but is surprised that Lucifer helped. He tells everyone that he doesn't want MC to be a demon or an angel, but a human who can someday work with himself to bring harmony to the three worlds. He wants MC to better understand all three worlds, not just stay in the Devildom. Barbatos then opens the portal to the Human World, the brothers say their goodbyes, and MC leaves.
After MC is gone, the House of Lamentation is back to normal, meaning everyone is arguing and missing MC. Lucifer asks if everyone is done tidying their rooms, then tells everyone to start packing, because they're going to the Human World.
MC runs into Solomon in a Human World park, where he asks MC if they're keeping up with the homework he gave them on fundamentals that sorcerers need to know. He also suggested earlier that MC take a babysitting job, and hands them the address of the people looking to hire MC. MC goes there to find a manor, and the door is answered by Asmodeus. Leviathan, Satan, Beelzebub, and Belphegor are there as well, and MC is so shocked that they use their pacts to make everyone "stay."
After calming down, Asmodeus explains that they're all spending their vacation in the Human World, and wanted to surprise MC, so they told Solomon to contact them. MC then finds Mammon hanging from the music room's ceiling because he gambled away all their money — and gave the deed to the house to some loan sharks — as soon as he got here. MC gets him down, then Asmodeus gives MC a tour of the manor.
The first room they visit is Asmodeus's private bathroom in the House of Lamentation. When the brothers decided to stay in this manor, they asked Barbatos to create portals to their favorite rooms in their home in the Devildom. Satan then finds them, and takes MC to the manor's home theater. He mentions that he and his brothers had been in the Human World since last week, but Asmodeus and Mammon insisted they keep it secret from MC until they could think of a way to surprise them. Leviathan comes in yelling about an emergency in the kitchen, and tells Satan to go there. He then asks MC if they want to see what it's like outside.
Leviathan shows MC the outdoor pool, then they go to his room to see Henry and game, but Belphegor interrupts, telling Leviathan he still has "a job to do." He then takes MC to their room from the House of Lamentation, which Barbatos also made a portal to. They both fall asleep there, then MC later wakes up in the living room in Beelzebub's arms, who'd carried them there.
The two continue to the twins' room, where Beelzebub retrieves some party crackers. Lucifer then sends him a text telling him to bring MC to the manor's balcony. Everyone is there to throw a party inviting MC to stay with them at Serenity Manor. Lucifer later asks MC to slip away with him, which MC can accept or refuse. If they do leave with Lucifer, he admits that he was planning this vacation to the Human World since MC asked them all for pact gifts.
After most everyone gets the idea to wake MC up that morning, Lucifer asks MC to go wake up Mammon. Then while eating breakfast, Lucifer reminds everyone they need to decide who will be in charge of what chores around the house. This leads to a "rock, paper, scissors" tournament involving Beelzebub calling forth a Rock Giant and Leviathan summoning Lotan.
After chores have been decided, another "battle" of rock, paper scissors takes place over the bathroom order. Asmodeus is excluded this time, as he has his own bathroom. Once all this is over, MC and Beelzebub leave to buy groceries for dinner.
Beelzebub wants to have roast chicken for dinner, and had Satan tell him all the ingredients. He tells the butcher he wants five whole chickens, and says "We're celebrating our first night living together." The butcher misunderstands Beelzebub's meaning, so gives him some relationship advice. The two then run into Mammon and Satan, and all four go to a restaurant Satan says has good pizza. Once there, Satan gushes about the restaurant being a film location for "The Twilight of a Great Family" - a drama TV show he loves.
After eating, MC can either visit bookstores with Satan, or a bakery with Mammon and Beelzebub. If MC goes with Satan, the two get lost in a bookstore and have to find their way out. If MC goes with Mammon and Beelzebub, they use Asmodeus's credit card to pick up a Mont Blanc for Asmodeus, but also buy lots of other food.
After returning to Serenity Manor, they all find Solomon waiting for them with homemade sandwiches and pastries, because Lucifer insisted Solomon make food for them after having to eat his food for lunch. While they eat, Solomon tells MC he thinks it's time they applied for a sorcerer's license, but the food is so bad that MC faints.
MC wakes up in their room, but when they leave it, find themselves in the Demon Lord's Castle. They encounter Little D. No. 2, who informs Barbatos they have arrived. Barbatos tells MC he'd connected their room to the castle earlier because Diavolo would like tea with them. Once everything is set up, Diavolo joins MC by the castle's pond, who tells them it's been quiet and boring since MC and the brothers left. He says Barbatos won't let him visit the Human World until he's made enough progress on his work.
Lucifer texts Diavolo asking for MC to return, as everyone has been waiting for them to make dinner. Leviathan, Beelzebub, and Satan bring MC to the kitchen to ask them about the modern appliances within, like a slow cooker and ice cream maker. They explain that while the Devildom has human world appliances like ovens and blenders, these newer technologies aren't familiar to them. Once dinner is made and everyone digs in, Asmodeus invites MC to a café called The Angel's Halo.