Some time ago i had an affair with my ex wife's sister. It wasn't planned nor was I interested in her sister at all.
It was summer and we on vacation in Pennsylvania near her sisters house. Her sister was married only a year . and my wife wanted to stay a few days with her sister and her husband so i agreed.
One morning my wife and I were in bed when her sister opened the door to our room , she was looking at my morning hard on. I sleep in my tight underware and at that moment I wasn't under the covers, so she got a very good look at my throbbing cock. I was awake and i saw her ogling my dick ,she had a grin on her face which was red as a beet , she slowly closed the door. My wife was sound asleep and didn't notice a thing.
later that day her husband went to work and my wife left to go shopping. I was in my bathing suit in the back yard when she came out with some
lemonade for me. She tried to give me some but dropped the glass in my lap and covered me with the sticky stuff. she laughed and said she was sorry , grabbed me by the hand and pulled me into the kitchen. she began drying me off with a towel and was rubbing me all over in an effort to get the lemonade off me. She started rubbing my cock and needless to say I responded with a raging hard on. I pulled down my suit and my cock popped out and pointed directly at her face. She was staring at my cock and got real close to it, I told her to make it bigger and she started sucking my dick. We did this for about 10 min when she grabbed my hand an took me into her bedroom. She took off her clothes and revealed a a full figure , big tits and a nice round ass . I jumped on her and spent the next hour licking her pussy and fucking her. I came twice and she did too.
After it was all over I asked what had happened, she explained that her husband has a very small dick maybe 5 inches at best and he was never able to please her. She admitted she watched me and my wife screwing the night before threw the door way to our room. She was impressed with my 7 inch dick and knew then that one way or another she was going to get it shoved in her pussy. She wanted to be fucked by me and no one else, she knew i would keep a secret because I had as much to lose as she did.
We never spoke of it and my wife and her husband never found out.
Through the years we managed to get away and screw our brains out but that was very rare.