Saori, a school girl, is molested on the notorious "molester train" of the Hanagawa line and rescued by another school girl who witnesses the act. The girl who rescues her turned out to be a new student of Yamashiro Gakuen high school, which Saori also attends. The mysterious new student Yuriko, is rumoured to be a "parent killer". Yuriko then leads Saori and her friends to hunt molesters on the Hanagawa line.
An incident in the past influenced Yuriko to absolutely distrust men, however Saori observes the world in a much more calm fashion, though she has a secret that only she keeps to herself.
Confronting their own desires, they go out of control. After a shocking encounter and separation between the two high school girls, their desires never to meet and reconcile, like train tracks never to cross. Those desires lead to a horrific end.