Short Story

Very bored and nothing to do, I David 32 great job my own home and single. My sister Martha 29 a plain looking woman average boobs and not overweight and shy around strangers live with me. I stayed in the city after university and got my job and haven't looked back since. Not much success with woman, but have had some success. Anyway it was a rainy Saturday afternoon and I was very bored and couldn't get excited by porn on my laptop. Then I came across a so called real brother and sister fucking site, I usually don't watch them as I believe they are fake anyway. But I decided to check one video at least, I wasn't expecting much from it. But the woman reminded me of Martha in body shape and I got horn watching her get fucked. I was going to masturbate to get off, but then I thought Martha's lookalike got me horny, why not try getting Martha to have sex with me. I wasn't thinking about it and didn't think what Martha might think. So I went to see her, she was reading and my hard-on had gone down a bit by the time I saw her. But on seeing her it harden up straight away, so I asked her would she do me a very big favor. Without even asking what favor she said okay, I then told her I needed to have sex as my cock was hard and wouldn't go down it was getting painful. She was shocked, but seeing the bulge in my pants and offered to get me off by hand, I lied and said I've already done that and it went down and then grew again almost straight away. She thought for a while and just when I thought she wasn't going let me fuck her, she said okay but you'll be my first. A virgin and I hadn't even thought that she might still be a virgin and so I wanted her even more. I didn't have any condoms and said I would pull out before I came. As it turned out I didn't and once she let me fuck her, I wanted her all the time. I've to live with my actions and Martha is happy being pregnant, even if it to her brother and the test show the baby is fine. One thing she can't get more pregnant she already is and with same surname, everyone thinks we're married. All except our family, but it's too late now and the baby is fine and they have now excepted our relationship.