The Kasshu House

The Kasshu House is the home of Domon Kasshu and his wife, Ultima Weapon: Prototype 0-1A, and is located a few miles out from Supreme City. His two children, Mikino and Auron Jet, used to live here, but moved out once they became adults. Domon's other wife, Kiyomizu Akane, also stays here whenever she has time off from work to spend with her husband. While it appears to be a seemingly normal house at first glance, it also contains the Sanctum Sanctorum, which is the greatest concentration of occult esoterica and mystical phenomena in existence.

Exterior
The Kasshu House seems to be a regular house when viewed from the outside. It is surrounded by trees and shrubs, and has a simple concrete walkway that leads to the front door.

Interior
While the house appears to be a one-floor building, it is actually much more spacious on the inside, as a result of Domon using his magic to make his house seem smaller from the outside than it actually is. The Kasshu House has 12 main rooms, with 5 of them being inside of the house itself. Two of these first 5 rooms are on the first floor, being the kitchen and the living room. On the second floor, there are 3 more rooms, which are Domon and Ultima's room, Mikino's room, and Xeraph's room, although both are now currently serving as guest bedrooms since Mikino and Xeraph left the house.

However, this is not all the house has to offer. There is a secret magical door located by the stairs that can only be opened by Domon that leads to the Sanctum Sanctorum, the personal additional residence of Domon which contains all of the magical related artifacts and knowledge that he has collected over the centuries. The Sanctum Sanctorum contains Domon's study, a meditation chamber, the mystical library, and the storage area for occult artifacts. In addition to these rooms, there are also the storage room, which is for non-magical artifacts, a magical bathhouse, a medical recovery chamber, and several doors acting as gateways to other dimensions.