At the Private Seikyō Academy, there is a legend that all students have heard. Sixty years ago, there was a girl who for some reason, was left behind in the old, abandoned school building to die. Teiichi Niiya one day meets a beautiful, mysterious girl named Yūko Kanoe at the old school building and gets a surprise—she's the ghost of the girl who died 60 years ago, but does not remember her past or how she died. Teiichi becomes determined to help her remember, and together, they seek the truth behind the gruesome legend.