The Bathroom (バスルーム Bathroom, lit "Bathroom") is an area in Versions 5 and 6 , located in the Mansion by going directly to the left twice from the Foyer. In Versions 5 and 6, it holds the Detergent or Soap, respectively.
The bathroom is a tiny room, just like the other room in its hallway. It has a main entry, and a 1-tile path into a toilet room, housing a toilet that when interacted with, will open the flap. Its walls are colored like the mansion's walls, and so is the floor. The carpet looks a lot like carpets in other parts of the mansion, just smaller.
This room, like the Wash Room, is impossible to escape from while being chased, as it is tiny, cramped, and has too little room to maneuver around the chasing oni to escape, even if you exit in time to supposedly maneuver around the oni that would be in the hallway. As such, do not go to this hallway when being chased unless you are able to maneuver around the oni in the hallway and escape further pursuit.
The only item to be found in the bathroom is Soap.