Nanami, a serious and dedicated teacher, is trusted and popular among her students. One afternoon after school, she invites a student who asked for advice to her home. Falling into the student's despicable and humiliating trap, Nanami's body gradually begins to react sensitively against her own will. Unable to suppress her shame, she is forced to expose herself as a mere pet for the student's carnal desires. This entire ordeal violently shakes Nanami's pure heart and innocent nature.