My wife's sister, Rika-chan, suddenly came to work one night at work. Apparently she had made a promise to her wife... For the time being, she was drinking alone, and before she knew it, she was in love with her. Then she suddenly confessed, "I've always liked my brother-in-law." Surprised, I tried my best not to cross the line, but I was overwhelmed by Rika-chan's aggressive momentum, including alcohol. Reason and instinct collide with the erotic temptation of a busty sister-in-law who approaches me to attract my attention!