Yui and Shinto had been living together for three years, but he hadn't proposed to her once until now. Their neighbor is Michael, a foreigner. Michael has a penchant for exercise, he always goes out with a pair of shorts that make his big dick look like he wants to break his panties and go out. Every time she saw Michael, Yui couldn't take her eyes off his groin. Once, while reading a book, Yui heard Michael cry for help. It seemed that something had bitten him, so Michael wanted to ask her to apply the medicine. And the place where it was bitten back was... his huge big cock! The process of applying the drug is not very normal. Yui constantly had to rub all of Michael's cock over and over again, so that after a while, Michael "shot" all the "poison" into Yui's mouth! Shinto and Michael get along so well that he decides to invite Michael to his house for a drink. Because of his poor alcohol intake, Shinto quickly fell asleep. This time, he seduces Yui right next to his boyfriend. Unable to resist this big cock, Yui gradually gets convinced by him and lets him fuck right next to her lover. And since then, Yui has continuously maintained this abusive relationship with Michael, even if her boyfriend proposes and wants to marry her, Yui can't leave Michael's big cock anymore.