At my friend's house, I was alone with my friend's polite little sister Riku and we decided to play a game together. I was shaken by the punishment game suggestion that the loser must do whatever she said, and I ended up losing. I wondered what cute command my little sister would give me, and she smiled and said, "Get naked...huh? She looked innocent, but she was actually a super sadist in the guise of a high school girl! She made one erotic request after another in polite language, and my hellish days of being milked like a raw dildo had begun.