Amane Asahide was on the fast track to getting into his choice school, but that changed when he got into an accident on the day of his entrance exams. Now stuck attending a regular school, Asahide would rather be anywhere else.

On a visit to the school's roof, he meets a lone girl named Kohane Negoto, who strangely seems to know a lot about him. The two begin dating not long afterward, and Asahide's school life seems to become somewhat brighter. But strange events soon begin to take place around him, and he begins to question whether his new girlfriend is responsible.