My Mei sister Mei is quiet and reserved, but she is fond of me. Although my parents don't know it, my sister has a strong sexual Kokoro, and even though I live alone now, I have been playing sexual pranks on her for a long time. One day, my parents decided to visit my parents' home to check on my grandfather's injury. However, my sister did not want to go, so my parents, hesitant to leave their teenage daughter alone, called me. Once alone, my sister and I crossed the line and had a passionate encounter.