After his father remarried, Yusuke, who didn't like his new mother Machiko. One day, Yusuke forcibly raped Machiko and recorded her with his smartphone, using the footage to blackmail her into becoming a fellatio sex slave. Yusuke's training escalated, and in his father's absence, he restrained Machiko with a senior delinquent and made her climax repeatedly with an electric massager and vibrator. Furthermore, with a senior with a large penis, they raped Machiko's large breasts. Machiko gradually went mad.
