My stepfather's slut teasing my wife, please forgive me now...

Mayu is the wife, who ends up staying at her husband's parents' house to fund her own home. I spent a peaceful life for a while... One day, my father-in-law Toshiro came home in high spirits after winning a 10,000-yen bet. Even when I see this, Toshiro, who is full of sexual desire, tries to somehow have a relationship with Mayu... He turns Mayu into the perpetrator of losing his bet, and takes advantage of his weakness and commits her in a flash. But that's not the case...