The Dare

My sister and I are always daring each to do things that we wouldn't have done with being dared too. Our fun as we called focused on David our very shy neighbor and referred by the boys, we dated a geek/nerd. David skinny 6'2" and if he played sport, he would've been great basketball. But he didn't sport and never dated either, always studying and he didn't a job after hours to make extra money either. His family was like ours well off and while we partied, he studied. My sister and I attend the same university as David, and she was 24 like David and I was almost 2 years younger. But we partied together, David was never seen partying and kept to himself. So, my sister and I made a bet to see who could bed David first. We believed him to be a virgin and we were totally wrong; he was quiet and kept to himself mostly. But we later found out he was very sexually active, fucking both his family's housekeeper 54 and ours 57. A long with his only female professor 52 and he was doing them all regularly. It turned out David wasn't shy just reserved, if he had nothing to say or wasn't interested in, he stayed away or quiet. Bedding David was very easy as he was always willing to fuck, also he has a large penis bigger than every other one I've seen or been fucked with. Both me and my sister were fucked by David, and it wasn't a one-off thing we wanted more of his cock. But my sister won, not the dare, but she married David a year and half later. But she has me join them every now and then for a threesome. I also help out when she is unable to provide sex due her being heavily pregnant. They have 4 children now and I'm single and 7 months pregnant to David. Which is my fault I hadn't kept up with my precautions and didn't realize until 4 days after. Our parents know who the father is and haven't complained as my sister hasn't and claimed it was a drunken threesome that caused me to get pregnant. Which could be true or not, it doesn't matter as I'm pregnant and that's the end of it. I hardly date other men at all and prefer being with my sister, her husband and their children. The baby is due early August at the latest and if he arrives on the second of August, he will have same birthday as me and I'll be 31 this year.