A father-in-law falls in love with his son's wife, Naoko, whom he should never be interested in... He observes Naoko's life and fantasizes about it. He also peeks at her having sex with her son and masturbating. One day, as he peeks at her masturbating, Naoko calls out to him... "Dad, I've known you've been peeking at me all this time." But instead of getting angry, Naoko invites him...