A woman named Ayumi, who is happily married but still feels lonely, witnesses her stepson Kazu's masturbation. Seeing his erect penis for the first time in a while, she becomes flustered and ends up using an electric massager to masturbate in front of his room. The previous night, Ayumi couldn't have sex with her husband, so she barges into Kazu's room while he is masturbating! As she listens to Kazu's troubles, she can't hold back the thrill of forced sex. She promises Kazu that she will 'cooperate even in hard sex' for his sake. Ayumi is then forcefully groped and raped by the transformed Kazu. Made to squirt with rough hand jobs and orgasmed repeatedly without a break, Ayumi becomes addicted to the stimulating sex... During her husband's absence, mother and son make love every day with raw insemination, filling each other's emotional gaps with their bodies, turning into an unforgivable parent-child relationship.
