‘I didn’t say anything about YOU doing that, did I?’ she asked, her nose touching the tip of mine, ‘Let me take care of that for you…’ She...pushed open the jacket of my suit, while I leaned forward, allowing her to slide it down my arms. As she slipped the jacket all the way off, her breasts rubbed against my chest. I couldn’t wait until I was also bare-chested, in order to feel her skin against mine. ‘You’re not in a hurry, are you?’ she asked, with that playful look that told me it really. I could never be in love with her. Even if we were the last two people on Earth, she was my sister. And she would never have me. I wiped myself off, and using my pocketknife, I marked a tally on the wall of the lab, as I did every day. There were eleven little marks on the wall. How many more would there be? How much longer could I go? I left then, so I wasn't looking at the screen. But if I had been, Felicia told me later, I would have seen my twin sister crying. Because she knew as well as I. Sitting in an easy chair was Tom Wiems. He had his cock in his hand and he was jacking himself off as he watched Mark fuck his wife Tammy on the couch. My dick got hard and when Darlene tried to pull me away I resisted - I wanted to see what was going to happen next. Tammy had her legs wrapped around Mark and her nails were digging into his ass and as he pounded into her she was making "oh oh oh oh oh" sounds each time he drove into her. I watched for several minutes until Mark said, "Here it. My hand was instantly under her skirt and my fingers buried in the thickest longest hair I had ever felt on any woman or man. Her entire bush was soaking wet and it dawned on me that there were no panties in the way either. My fingers stroked between her thighs and zeroed in on her full long labia and huge swollen clit.I broke away from our kiss and she was reading my mind as she lifted her skirt to her waist. Her bulging muscular thighs exposed, she raised one of her perfect athletic legs to.