Yuna lives a happy married life with her husband. One day, after a fight with his wife, her father-in-law comes to live with her for a while. Her husband, who cares for his family, accepts the move, but Yuna finds it difficult to accept it. Yuna's dissatisfaction grows, and her father-in-law's sexual harassment escalates until she crosses the line...She becomes addicted to perverted sex with her father-in-law, whom she was supposed to hate.