The Poltergeist Mansion (Sōreiyashiki, 騒霊屋敷) is home to the Prismriver Sisters. It was formerly the mansion of a human aristocrat in the outer world, but was transported into Gensokyo by the invocation of an unknown ritual.

Although the poltergeists that reside within are clearly not alive, the mansion seems to exist outside of the Netherworld.

Not much is known about the mansion itself beyond the fact that its inhabitants are noisy and that its precincts are probably dangerous to mentally unprepared visitors.