As a ronin student, I'm currently living with my older brother and his wife. I made a deal with my sister-in-law Airi: if I score 100 on my exams, she'll do anything I say. While my brother is away, I turn Airi into my personal sex maid. At first, she acts tsundere, saying "It's so embarrassing..." but gradually she becomes completely dominated by my cock. We experience various erotic acts—full-body foam baths, ass massages, devoted blowjobs, toy torture leading to multiple orgasms, cowgirl position creampie sex—and as Airi moans, "Don't go so hard... I'm cumming!", I too become increasingly addicted to the pleasure. Ultimately, I realize that no matter how married she is, she's still just a woman, and watching her become utterly submissive to my cock is the ultimate thrill.