Alone with my friend's polite adult sister Riku, I agree to a video game wager where the loser must obey any order. I lose and expect a cute request, but she calmly commands me to strip. Beneath her innocent adult-student role-play look is a vicious sadist who humiliates me in formal language, issues increasingly sexual demands, and uses me like a living dildo, milking my cock and making me creampie her.