My Nudist Family.

We were a nudist family. In summer my sister would lay naked with my father and I would lay naked with my mother as we all watched TV together. It was normal for us but we mostly hid it from everyone else. My father would quietly fuck my sister in front of us often. They would be facing the TV spooning naked and then they would start quietly fucking. They made an effort to not show any penetration but it was clearly happening. Often they would do it when my mother was asleep, as she fell asleep easily in front of the TV. She definitely knew though, as it happened when she was awake as well. My sister was like a free pass for my father. My mother didn't seem to mind. It was never discussed. Once time when they were fucking while she was asleep, I got turned on and my hard-on pressed against my mother's ass as she was in front of me. It wasn't long before my tip was rubbing against her shaved pussy, and it started to go in. I froze as I realised that while my father was fucking my sister in front of me, I now was inside my mother for the first time. Just the thought of it all made me cum despite my best efforts to hold back. She got up straight away after I nutted just inside her. I had to quickly hide myself, as she did. We never spoke about it, and it only happened a few times. I just wanted it to turn into group sex, but it never did. I also never got to fuck my sister which I regret. She did blow me one time which was random but awesome. It's a shame I nutted so fast, but she did it when she walked in on me when I was jerking off in the bathroom. I wasn't far from cumming when she walked in and without hesitation, dropped to her knees and took me in her mouth. I came within about a minute. I was always to frightened to make a move on her, because was worried about my father being jealous if he found out. I think my mother let me fuck her out of sympathy because she knew I was getting turned on by my dad fucking my sister on the next couch. Maybe that's why my sister swallowed my load that time. I don't know. I just know it's all over now, as we've both moved out of our parents place. Maybe my sister still get railed by my father and I just don't know. They were pretty kinky times though, that only stopped about a year ago.