Due to her remarriage to his father, Ryouko becomes the stepmother of Kotaro, and their relationship gradually transcends normal family boundaries into an overly protective, intimate bond. Her constant attention begins to control Kotaro's daily life, leading to an abnormal routine where Ryouko performs blowjobs on him each morning to relieve his erect state so he can urinate. As time passes, Kotaro's demands grow increasingly intense, eventually pushing them into a forbidden, taboo relationship.