With her husband away on a solo assignment and her independent older adult son living elsewhere, a mother spends her days alone with her younger adult son. Her secret problem is that he has begun demanding her body. Feeling guilty for all the sacrifices she made him endure in the past, she cannot push him away and lets their relationship drag on. Then her older adult son Hajime returns home after losing his job. She believes his presence will finally give her a chance to end the twisted affair, but...