Since the afternoon, mother has been spending intimate time with her daughter when she's caught masturbating in the hallway by her son. Realizing she's been seen, mother becomes even more aroused and ends up getting caught by her daughter while using the daughter's vibrator. Harshly scolded by daughter Kumiko, mother Kumiko Niizawa remains restless, takes her son's hand, and heads toward the sofa. Each step forward leads deeper into tangled family bonds and forbidden desires...