The following is a true story - I hope you enjoy it.
*
I'd had a vasectomy after my kids were born. Since then, I'd gotten divorced then remarried. My second wife, Gina, was wanting to have kids of her own. We discussed attempting to reverse the vasectomy, but had pretty much decided against that. Reversal wasn't likely to be successful, anyway. What we didn't know was that Gina was sterile. Had we known that, this might never have happened...
We had fooled around with a single man on occasion. But, Gina tried to be careful. He had a rather distinctive appearance and had she gotten pregnant from him, it would probably have been obvious that the baby wasn't mine. So we decided to ask my brother, Jim to step up and try to get Gina pregnant. We called him and asked him, point blank, if he'd come over to our house and fuck Gina ... try to get her pregnant. He couldn't believe we were asking him that. After asking several times if we were serious, Jim agreed to come over the following weekend.
When he arrived, we just hung out together for awhile - drinking beer (at least Jim and Gina did - I stayed pretty sober.) After we put the kids to bed, we hung out a little longer to give them time to get to sleep. Then, we all went to our bedroom and got in the bed; Gina in the middle, Jim and I on either side. We still had our clothes on at this point.
Gina started kissing me and I was fondling her tits through her top. Then, I started pushing her top up to expose her tits. She rolled over and started kissing Jim. I kept pushing her top up and then pulled it off over her head. Jim put his hands on her bra - and started fondling her tits through the lace of her bra. I was pressed against her back. My cock was already hard and I was pressing it into her ass, humping her ass through our jeans.
I unhooked her bra, and slipped it off exposing her tits to Jim. They were kissing each other and he started kissing her neck, shoulders, and working his way down to her tits. She gave a satisfied moan when he took her nipple into his mouth. At this point, I thought I'd be the first to get naked so I wouldn't miss anything as we went along. So, I rolled off the bed and stripped. Then, I got back into the bed and snuggled up to Gina's back. This time, my bare cock was against her jeans.