On her sixteenth birthday, orphan Himari Momochi inherits her ancestral estate that she's never seen. Momochi House exists on the barrier between the human and spiritual realms, and Himari is meant to act as guardian between the two worlds. But on the day she moves in, she finds three handsome squatters already living in the house, and one seems to have already taken over her role!

Himari Momochi inherits Momochi Hiouse, an estate which exists on the barrier between the human and spiritual realms. Himari and Aoi's summer together has passed by in an instant. When Himari wakes, she discovers that Aoi has been absorbed by Momochi House. The building begins to collapse as Aoi tries to release Himari and the shikigami. Is Aoi lost forever or can Himari save him?