Fuuta Okeya is a normal boy, except he sees ghosts. A beautiful girl, Kouko Ishigami, transfers into his class, but acts aggressively towards him. Fuuta tries to get along with her, but ends up failing after she sees the birthmark he usually keeps covered. She then declares him as her enemy, his birthmark as a cursed mark, and claims that they have a long history together in their reincarnations.