So I grew up in Forster care. I met my father when I was 18. His girlfriend had a daughter that was too fucking sexy. She was 17. Her body was do perfect i couldn’t even believe myself. She had a “husband” she’d had a kid with. But he was such a piece of shit to her…. she did everything he asked her too. I was out back splitting wood. With each swing of the Mawl I could here this faint whimper sound…. I started to investigate it was a cool evening night in the summer. I turned the corner and through the window I literally came face to face with. “Stephanie” she was laying on her back with her legs spread wide. She was being fucked silly by her “husband” except I hate to pick fun but this guy had the tiniest pencil cock I’d ever seen. You could tell she was really just “acting” and not truly enjoying herself.. then she looked up. We locked eyes. His back was turned to me. Her eyes got huge first with surprise then it’s almost like she was egging me on. So I pulled out my cock… now I’m close to about 9 inches fully erect and thick too.(I will prove it if necessary) when she sees the sheer size of me in my hand she locked eyes on my cock as I begin to stroke it. Her moans become louder her dude start banging her even harder thinking that its for him. I’ll never forget this as long as I live. Her face turned bright red as she strained against her own orgasm. Husband ALL STOKKED apparently that was the first time she’d ever gotten off with him haha. She tells him shes gotta go to the bathroom real quick and nodded me to follow her. She snuck outside still but naked and leads me into a 16foot prowler trailer. My cock was still so hard at the site of her body perfectly tight everywhere.. she thrusts her lips around my cock causing my knees to buckel… I couldn’t take it I bent her over the table in the trailer and slammed myself into her. I humped a total of three times and I could feel her pussy explode. At this point it’s so hot and and so wet I was about to bust. I hummed a total of 5 more times and we came together. To this day I’ve never had a pussy soooooo tight… so the big surprise is is that weeks later and we’ve been banging behind everyone’s back the whole time we find out through a string of events that my father had cheated on my mother with Stephanie’s mom in high school… long story short we found out we’re siblings… YEP brother and sister. I’m 30 now and we still fuck a couple times a year behind our significant others backs haha I can’t help myself