"Harder! You fuck like third grader!" Izzy growled at me, turning her head. Damn it! She was really determined to piss me off. Getting angry, I slappe... her ass hard, leaving a red mark the shape of my hand, then I slammed my dick into my sister so hard, she almost slipped on the wet floor. I kept pounding her cunt, smacking her ass when she needed it. When Izzy started moaning and I could tell she was about to cum, I leaned forward and grabbed her tits, fondling them and tweaking her nipples as. “Priest,” she said. “If I wasn’t your sister, would you want to date me?”Oh ... dear ... God?“Your corollary has no basis,” I said to her.“What’s that mean?” she asked, getting on my lap as Shirley just had been.“Sorry ... you can’t not be my sister, so the question is moot.”She looked at me funny, so I did the obvious and kissed her. It only lasted maybe a second, so I said, “Did that feel romantic, or like your brother just kissed you?”She got all glassy-eyed, and said, “Yes,” to both. I tried to slide my eyes as far to the left as they would go without moving my head. It didn’t really work but I caught a glimpse of another man standing there. Again there was no sound of piss. I rubbed myself slowly and continued looking down, and then glanced over. He was clearly rubbing his cock too, and it was very thick.I froze for moments, suspended in a state of unknowing, and then turned towards him letting him see me playing with myself. My cock wanted to explode. He turned and let me. ’ John had to be her Uncle John! Oh, my God! They were doing ‘IT’ in his office!’ Amy grew more daring about the situation, and moved closer to the door. Carefully turning the knob, she turned it easily with only a soft click, and waited for them to make some more noise before opening it a crack. That was enough for Amy to glimpse inside and discover she could easily view half the room. Two people were on a couch. No! The woman was on the couch, the man, who must be her uncle, was leaning on.