Suffering from her father-in-law's sexual harassment, wife Satomi finds herself increasingly frustrated due to her husband's busy work schedule. One day, she discovers a pornographic magazine in her father-in-law's room, becomes aroused, and impulsively begins masturbating. Caught in the act by him, he forces her to wear a chastity belt and imposes strict conditions, controlling her sexuality. While caring for her father-in-law, Satomi is continuously teased and denied release, subjected entirely to his whims. Eventually, she comes to accept her own deviant desires, leading to a disturbing progression in which she desperately pleads for the elderly man's penis—once utterly repulsive to her.