After a painful breakup with her fiancé, Yumi tries to focus on her role as a teacher while navigating growing personal turmoil. Her situation escalates when the vice principal begins making unwanted advances, drawing in several students and leading to a coercive trap. Forced into a secret agreement that binds her, she seeks help from the hesitant Katsutoshi and his spirited girlfriend Keiko. Yet the mounting attention from those around her makes escape seem increasingly difficult.