Single mother and busty housewife Kondo Ikumi, struggling with her son's inability to emotionally detach from her. As her well-endowed breasts are repeatedly groped by her growing son, she begins to feel unexpected pleasure from the acts. One day, her son catches her masturbating to relieve her heated body—and from that moment on, he starts groping her breasts from behind whenever she's doing housework. Despite her protests of "No, stop it...!!", her warnings are ignored as her son continues to indulge in the forbidden pleasure again and again.