During summer vacation at university, I went back to my relatives' house and found my grown-up cousin, Sayaka! She still treats me like a kid, and her defenseless chest and ass are too sexy! When I decided to stay the night, Sayaka came to see me, who was so horny I couldn't sleep! When I couldn't hold back and attacked her, the sexual desire that my cousin had been suppressing in the countryside overflowed and we had sex in sweat...