I love my father-in-law more than my husband...

Rio is married to Kazuyuki, the only son of Shigeo, who was her boss at work, and lives a life without any complaints. However, Rio had a feeling that she couldn't tell her husband. Those are feelings for Shigeo... His son Torio Kazuyuki got married because he wanted to be with Shigeo. And while Rita keeps suppressing her feelings, thinking that it's okay just to be close to him, the more time she spends with Shigeo, the more she can no longer suppress her mind and body, and eventually seduces Shigeo...