Mean sister's male pinch! ～My boyfriend's brother is a sex toy that can be exploited as much as I want!～

The heroine, Airi Uemura, has been in a relationship for nearly 10 years since their mischievous school days. She was troubled by her physical relationship with her older boyfriend, Makihara Shingo. Airi is a former delinquent, so she'd rather blame than be blamed! They both felt that they were incompatible due to their sadistic tendencies. They are thinking about getting married someday. An indoor date where we saved on the cost. Taking advantage of the fact that no one is around, Shingo approaches her and they start having an affair. After finishing their affair, they encounter Shingo's younger brother, Shinji, who has left work early due to an injury. Later, I bumped into Shinji on my way home from work and asked him about the other day... He was certain that the whole incident had been spied on. Airi, shocked and excited by being seen, takes Shinji into her room... She humiliates Shinji by using him as a toy to satisfy her sexual desires.​