Iori accidentally discovers her son masturbating and is deeply moved by the sight of his mature body's reaction. Mesmerized by her son's erect cock, she returns to her bedroom and begins masturbating. Hearing strange noises from her room, her son becomes curious and quietly peeks inside—only to witness his mother pleasuring herself. Overwhelmed, he confesses, "I can't hold back anymore," and Iori gives in, telling herself, "Just this once." But unable to restrain himself, the son pleads, "This should be okay, right?" as he requests anal sex. This impulsive decision drastically changes the mother and son's relationship forever.