A close family of three. However, Shiho has a secret that she cannot tell her husband. She was pushed down and had a physical relationship with her son. She thought it would be a one-time thing, but her son didn't think so. When his father is not looking, the son approaches his mother. Unsatisfied with her nightly activities with her husband, Shiho is on the verge of succumbing to temptation. One day, Shiho is masturbating while remembering her affair with her son. Her son finds her. "You really want it too, don't you?" he says, making his mother hold his enlarged penis...