Ruri Saijo married a man who has a son from a previous relationship. The son is a reclusive shut-in who resents Ruri and refuses to show his face. When she peeks into his room, she discovers photos of herself and videos of her secret affairs. Using this as leverage, the son begins blackmailing her, groping her massive breasts. From then on, Ruri is completely under his control, forced to serve as his sex slave whenever her husband is away. With a sinister gaze, the son continues to torment and humiliate her, driving her deeper into degradation.