After her mother-in-law passed away, Maki was forced to look after her father-in-law, but she was dissatisfied with the fact that their nighttime activities had decreased. Her father-in-law continues to look at Maki, who is devotedly taking care of him, with lewd eyes. When he witnesses Maki indulging in masturbation, he can no longer bear it and attacks Maki! However, Maki becomes addicted to the intense sex with her father-in-law, who is different from her husband, and becomes a captive!