Mio Kimijima, a dedicated female teacher, witnesses a shocking scene at school when she sees a colleague stripped naked and bound by students. Driven by strong moral principles, she bravely offers herself as a substitute, exposing herself fully naked and forced to masturbate in front of the students. The next day after school, she is lured to a hotel by the same students, where she is drugged with aphrodisiacs and brutally raped. This act only intensifies the students' lust, escalating into further torment—tying her up in the classroom and making her climax against her will. Even as she tries to maintain her composure and continue teaching, the students surround her one after another, subjecting her to relentless humiliation and abuse. This series of events shatters her ordinary life completely.