My parents remarried and I got a big-breasted step-sister. I still couldn't think of her as my real sister... So when we went out together, or stayed at a hotel, I couldn't shake the feeling that I was going on a date with a girl and going to a hotel, so I guess it was inevitable that I crossed the line. She showed me her soft breasts, and I inserted my rock-hard cock raw into her vagina. My parents would never approve of this relationship...