You seem to know about sex, but you're a virgin when it comes to being on the receiving end..." My sister, the nymphomaniac, treats me like a virgin despite my newfound confidence in sex. Despite my resistance to this shocking "virgin treatment," I find myself getting more and more engrossed in the pleasure of being taken, taught by my teacher. Slow pistons and explosive speed pistons in the cowgirl position with teasing attacks! None of these nymphomaniac punishments are things I've experienced before, and my unpunished M-type pervert body is being developed more and more...