A forbidden extramarital affair that must be kept secret from his wife and daughter. [Episode 1] Makoto is alone with his mother-in-law after his wife goes out with a friend, and he finds her masturbation toys... [Episode 2] While taking care of his drunk son-in-law, Chika is pushed down by his wife and they end up having a physical relationship... [Episode 3] When his wife goes out to a girls' night out and they are left alone, he ends up having sex with his mother-in-law... [Episode 4] They talk about their sex lives with their late husbands, and Honoka's strong sexual desire is discovered by her son-in-law...