House of Lamentation
The House of Lamentation is a large mansion located in the Devildom, and is where the seven demon brothers Lucifer, Mammon, Leviathan, Satan, Asmodeus, Beelzebub, and Belphegor live. Beginning after their acceptance into RAD's student exchange program, MC also spent time living with them.
In Lesson 1-7 (OM), Mammon explained that the House of Lamentation is the RAD dorm reserved for student council members. While the building originates from the Human World, Diavolo mentioned in the phone call Let's Stay in Touch that it was Lucifer's idea to move the building to the Devildom.
The house's architecture looks to be Gothic Revival, and there are seven headstones in the front yard. There's also at least one tree within the house, for there's one in the MC's room and one seen in the hallway. It's unknown if these are both the same tree.
According to Mephistopheles in Lesson 33-6 (NB), the House of Lamentation was built atop an "especially evil plot of land" that is infamous throughout the Devildom. The land now belongs to the royal family, but according to legend, this land was once home to "the father of demons," aka Nightbringer.
As mentioned by Satan in the chat Hot Spring Survey, there are mountains behind the House that contain hot springs with 200-degree water "straight from the source."
- Asmodeus's Bathroom
- Common Room
- Communal Bathroom
- Dining Room
- Entrance Hall
- Guest room
- In the chat Slumber Exchange 7, Mammon mentions a guest room.
- Laundry Room
- Living Room
- It's connected to the Entrance Hall, for the mirror can be seen in the entryway.
- As mentioned in the Devilgram The Avatar of Sloth, when the brothers first moved in, this room contained one of the two TVs in the house -- the other being in the spare bedroom that was MC's room in the original game.
- Lucifer's Study
- Can be accessed from a secret passage in the library.
- Music Room
- Underground Tomb
- As seen in Lesson 40-20 (OM), the tomb has an emergency escape route that leads to the far reaches of the Devildom.
- Lucifer's room
- Mammon's room
- In the Devilgram Proud Brothers, it's stated that Mammon's bedroom is next to Satan's.
- Leviathan's room
- This room was not always located where it is now, as Leviathan mentioned having moved rooms in Lesson 7-17 (OM).
- Satan's room
- In the Devilgram The Avatar of Sloth, Belphegor mentions that this was originally going to be his room until Satan came along and Belphegor was forced to share with Beelzebub instead.
- Asmodeus's room
- Beelzebub's and Belphegor's room
- There is a secret passage in this room's closet that leads to the Underground Tomb.
- MC's room
- The room has a desk within it, and one of the drawers of which possesses a lock. Lucifer suggested MC keep their valuables within it in Lesson 2-4 (OM).
- Their room has its own bathroom, as alluded to in Lesson 4 (OM) — when Mammon left his toothbrush there — and in the chat Bath Time with Asmo 1.
- Their room is located next to the kitchen, as evidenced in Lesson 5-2 (OM) when Beelzebub destroyed a kitchen wall shared by MC's bedroom.
- According to the chat Changing Rooms, MC's room is separate and at some distance from everyone else's rooms.
- As mentioned in the Devilgram The Avatar of Sloth, when the brothers first moved in, this room contained one of the two TVs in the house -- the other being in the living room.
- Lilith's room
The House of Lamentation was originally built in the Human World on the outskirts of a village. The people who previously lived there were a married couple with their seven children, and their servant.
One day, a terrible tragedy struck inside the house. Every family member was brutally murdered in a different way, in a different room, and the servant had hung himself in his own room. The only survivor was the eldest son, who claimed the servant committed the crimes. The authorities deemed the case closed, but rumors started spreading that the eldest son was on bad terms with his family. It was then believed that the servant tried to stop him but was killed and framed to be the scapegoat for the murders. The son continued living in the house until he died of old age.
Afterward, there were figures seen in the windows, and screaming and arguing could be heard despite being vacant. Because of the dark history, the mansion became known as the "House of Lamentation."
Eventually, the mansion was transported to the Devildom and became a dorm for the demon brothers.