The Demon Prince of Momochi House.

Himari’s 16th birthday will be one she never forgets. Unexpectedly, she receives a will detailing her inheritance of a mysterious estate: the Momochi House. She arrives only to discover that the home was built on the cusp between the human world and the spiritual realm. There, she encounters Yukari, Ise, and a peculiar boy named Aoi, who seems to be concealing a shadowy secret.