Rei Aoki, a married female Japanese language teacher at an all-boys school, one day loses control and urinates in desperation. A student catches her in the act and seizes the opportunity to blackmail her, forcing her into humiliating sexual acts. As the daily abuse on school grounds grows increasingly intense, she struggles internally to resist, yet becomes aware that her body is responding against her will. Ultimately, she is penetrated by the student, squirts in front of him, and comes to experience the perverse pleasure of being watched during sex. At that moment, she whispers, "I'm sorry… I'm sorry…"