I have been married to my wife Karen for almost 10 years now. We have a wonderful relationship and are very open with each other, emotionally and sexually... especially sexually.
Having been married for this amount of time I have known her whole family for years. We have spent a lot of time together over the years, even vacationing together from time to time. Her parents are Sally and Rick, who like me and their daughter got married rather young so they are only in their mid-forties. They both stay in great shape and look good in their bathing suits. Karen's younger sister Molly is 4 years younger and just got married two years ago. Molly is a 5' 7" blonde who works out regularly and has a great body which I have been noticing since I met my wife. She has one of the best asses I have ever seen, legs for days and a small D-Cup to top it off. We tend to see a lot of each other since Karen and Molly are close. As I said Molly was married about two years ago to a guy named Joel. Joel is a great guy in great shape. Although he doesn't make a lot of money working as a city administrator he loves his job and allows Molly to stay at home in anticipation of her becoming pregnant.
Molly has been trying to get pregnant ever since they were married with no luck. Her Gynecologist did some testing and it seems everything is working as it should be. Unfortunately that is the extent of the testing her and her husband can afford at this time. What makes it harder is Karen never had any issues getting pregnant anytime she wanted. Same went for their mother Sally.
My wife had been talking all of this out with Molly over the last few years, trying to comfort her, but nothing they are trying is working. She tells my wife they have sex all the time and Joel hasn't been jerking off at all. When they are done she is leaving his cum inside for as long as possible but it just isn't taking. According to Karen they are at the point where they would do anything to get pregnant. They would have no problem going down the fertility path but it just too expensive. Karen being the older sister wants to do everything she can to help.
One day Molly was over at our house talking to Karen about all the stuff again, even getting into the details and positions they are trying in their private sex life. This doesn't in anyway bother Karen, it may even turn her on a little. Karen did something that afternoon that I didn't expect at all, she offered my sperm to her sister. Her sister was on board with trying it but didn't understand how she was going to get my sperm inside her body. Karen explained to her that it would just have to come directly from me, that would be the least expensive way to go. Instantly Molly knew what she meant.
After I got home from work later on in the evening and Molly had already gone home she floated the idea over dinner. I almost lost it, there was my wife asking me to do her sister a favor by cumming inside her, likely multiple times until she conceived. This was kind of a dream come true for me. My first question was what Joel thinks about the whole situation, she said he and Molly were going to discuss that evening. Next I asked, assuming Joel was on board, where she would be during the whole ordeal, as open as she is sexually she said she had no interest in seeing her sister get fucked. So I told Karen I would be on board but not with out Joel being completely okay with it.
As suspected, Joel and Molly had talked it over the night before just as Karen and I did. Molly and Karen got together the next day to talk it over. Turns out Joel is on board but he wants to be there while it is going on. Seems like he may not mind watching his wife have sex with another man. Unfortunately for Joel he would not be able to finish inside her after me, no matter how horny, we don't want to confuse the sperm already inside her. Karen called me at work with the good news and we decided to set it up for Friday night.
The rest of the week went smooth but was rich with anticipation. Karen and I fucked everyday leading up to Friday. It seems like it was a real turn on for her to have me fuck Molly. On my end I couldn't wait to see my wife's younger sister naked taking my cock, something I have dreamed of for a long time.
Friday night finally came. After work I went directly to Joel and Molly's house. When I got there we exchanged pleasantries and went upstairs. I decided it would be good if I showered before getting into it. Molly went to get me some towels and I went to the master bathroom and turned the water on. As I was getting into the shower Molly came in to drop the towels off and got her first glance at my naked body. All she said was "wow Mike this looks like it could be fun for both of us". I wasn't really sure what that meant. I have never seen Joel naked so I have no idea what he is packing. After that comment I had a decent hardon going but finished my shower and dried off.
I came out of the master bath in just the pink towel Molly had provided to see Joel had gotten home from work in the meantime. Molly was in a thin bathrobe clearly without anything underneath, her perky nipples were showing through the thin material, she was looking forward to this. Joel also seemed to be in good spirits, he was wearing gym shorts and a white t-shirt. I asked them how they wanted to get started, Molly asked me to drop the towel. Now I don't know Joel very well but I have no problem being naked around other men, I would never date or kiss another man but I had done stuff with men before so it was no big deal for me. I have no idea where Joel is on the spectrum but seeing me naked, half hard, didn't seem to bother him in the slightest and was a bonus for me.
After I dropped the pink towel Molly came over, still in her robe, and grabbed my cock and started to play with it a little until I got a bit harder. She commented that I seemed ready. I stopped and turned to Joel who I could tell had a raging hardon and asked him if we are still good to go. He smiled and gave me the thumbs up, he then walked over to Molly, my dick in her hand still, pulled her robe off and started kissing her, she immediately embraced him and I got an eyeful of her assets for the first time. She was clearly turned on!
Molly laid on the bed and I got up there with her. Joel was still kissing her and her body. He was making his way down her neck while gently massaging one of her wonderful breasts. I grabbed my cock and got in-between her legs. I started to rub the end of my cock on her pussy to get a little lube going. Still amazed at her body and that I get to fuck it. I started to press a little harder against her as if I was going to insert it, unexpectedly Joel pushed my hand away, he said to hold up, he was going to have to help with that. I was very confused for a second then he did something even more unexpected, he pushed my hand off my cock and grabbed it with his hand, he gave it one or two strokes then guided it into his wife. After the head was in Molly told him to go slow since apparently I was larger than Joel and she isn't used to me...yet. so Joel continued to squeeze my cock as it is being inserted. I had no problem with him doing this, I don't mind having a good looking guy like Joel grab my hard cock. Finally I was most of the way inside Molly and he let go and put his hand on her pussy and started playing with her clit. At this point his mouth was on her perfect nipple sucking away as I was trying to pump in and out of his wife. After that it was mostly non-eventful. After another 15 minutes or so I came pretty hard inside Molly. I left my cock in after cumming for a few more strokes before I pulled out, honestly I was still pretty hard and horny. As soon as I pulled out she palmed her pussy as to not let any cum drip out, and thrust her legs into the air to try and help the swimmers out. It was a pretty site.
I felt pretty bad for Joel, he obviously had an unused boner with no where to put it. I went back to the bathroom and washed my cock off and came back out to see Molly sucking his cock like it was the last cock she would ever suck! I gave Joel a thumbs up and grabbed my clothes and took off. I figured they would need their time together after that session.