One advantage of having a highly sexed and orgasmic wife, besides the obvious of getting lots of fabulous sex and feeling like a hero because she always comes, is that she probably is more readily agreeable to sharing, and threesomes and foursomes, than the average woman. That certainly is the case with Abigail. We met at school when we were both 16 and have been together ever since, having much more than the average frequency of sex which began only a month or so after we met when she demanded we do it because her older sister had just done it with her boyfriend and was bragging to her about how much more grown up she was. I was the beneficiary of their sisterly rivalry and she took to sex from the first. I've been a tradesman since leaving school at 18, branched out a few years later when I became skilled, and have built up a good business for myself, now employing over 40 people, so there's money available for some luxuries for us. We're both 38 and in the prime of our lives. I am still physically active in my trade working alongside my men two or three days a week on difficult jobs, and Abby is just as fit as me from her time at the fitness centre doing weights, running, and Yoga. The point is we're very fit, trim, and energetic, and easily pass for being much younger. Early in our marriage, at her request, I started sharing Abby, usually with a businessman on travel to our area. We would meet at a hotel bar for drinks and then up to the room for 'fun'. I would watch as he made her come with mouth, fingers, and then his cock. Being highly orgasmic, she would come several times when he was up her with his cock. I would then send him on his way and we would stay for another hour or so, fucking and cuddling and fucking and cuddling - you get the idea. A few months ago, we went on holiday to the 'States' that included a week cruise down the Baja Peninsula south of California with a stop at Cabo. When the ship docked that morning at around 9, Abby and I looked for a bar. We went to one on the beach and had a blast! We met a younger American couple in their late 20s who were also from our ship, and Fran and Abby took their tops off for the Mexican 'bandito' who was going around the bar playing his guitar and looking for hot wild women. His mate takes photos and sells them to the husband or boyfriend. We hit it off with Fran and Ed, and by the time we all had finished our first drink, Abby and Fran were 'bosom buddies' as Fran called them. As our two wives chatted together intimately, Ed and I each admired the charms of the other's wife since they kept their tops off with their breasts covered only by the decorative pasties the 'Bandito' had placed on their nipples for the photos. Both women looked totally fuckable just sitting there having 'girl talk'. Ed and I started talking during our second drinks and, by the third drinks, we had discovered we had wife sharing in common. I'm not sure which one of us suggested it, but we didn't have to be back onboard until 4, so we had about five hours for some 'fun'. Ed and I quickly came to an agreement on the kind of fun we wanted, and hustled our wives down the street to a big chain hotel, got us a room with two king sized beds, and had the wives inside the room before they could object, which was unlikely after three big drinks. We found out later they had overheard us discussing this and secretly agreed with the wife swap. They played along that it was a surprise when we suggested we trade wives for the afternoon and watch each other fuck. Ed was certainly impressed when he had the rest of my wife's skimpy outfit off, admiring with lust her prominent mound and the light colored hair around her beautiful pussy, as was she of his thick seven inches. Being younger, Ed was a lot less controlled than me and they were already on their bed while Fran and I were still slowly kissing and caressing each other's parts as we peeled off each covering piece of clothing. When we finally were completely naked, Ed already was on his stomach between Abby's raised and spread legs eating her. Abby loves good oral sex and by the look of her body language, Ed was doing it to her satisfaction. I told Fran it looked like Abby would be coming soon and we should watch them, so we lay naked on our bed and watched them. She lazily wanked my cock and I slowly fingered her wet gash. Abby soon came from his tongue and he immediately mounted her, shoving his cock up her with several partial thrusts. She snapped her head back and gasped with each of his penetrating thrusts until he was all the way in. She likes doing that even if the cock doesn't cause her pain or discomfort since it enhances her pleasure from the initial contact. Fran and I continued watching them instead of beginning our own session since it looked like they were going to give us an energetic show, and we weren't wrong. Ed fucked Abby with abandon and she fucked him back just as energetically with her arms wrapped around him and using her legs for leverage for her hip thrusts. They were really into it and totally ignored us. Within just a couple of minutes Ed gave Abby the first of many comes she would have during the next few hours. She came with loud moans and groans, then came again only a minute or so later when Ed continued fucking her. I told Fran that Abby was especially horny and when she's like that, she can come every minute or so if Ed continued fucking her. And it seemed Ed sensed that, for he just fucked her and fucked her, giving her serial comes. By the time of Abby's third come, Fran increased her wanking of my cock and said, "What about me? I know you're enjoying watching your wife get fucked, but it's time you fucked me!" She lay back pulling me with her by my cock. I gladly followed her lead and got between her legs. When she realized I was going to eat her, she stopped me and said, "No need for that. I'm so horny from watching them, I'm already swollen and sopping wet. Just get in and fuck me!' My kind of girl! I mounted her and slid my six plus inches up her and hoped it would satisfy her since it wasn't quite a long as her hubby's. No worries. She moaned with passion as I slid up her and moaned, "God, you feel good!", then immediately wrapped her heels behind my thighs and used her legs to pull my hips deeper against her on each of my strokes. We fucked vigorously for several minutes, and she came the first time at the same time as Abby came for the umpteenth time from Ed's continuous fucking. Ed and I fucked each other's wife for the next couple of hours or so, ending with a final session with our own wife. When we returned to the ship, we all agreed we would have a repeat performance onboard sometime during the three remaining nights of the cruise. That night we had dinner with our girls as usual and the next day was a day at the beach at the next stop, which we spent as a family. That afternoon, the next swap was arranged for the next night. That next night we had dinner with Fran and Ed and went to the ship's show. We returned to our respective cabins with each other's wife. Fran and I were already quite familiar with each other's bodies from our first swap, so this night wouldn't be quite so erotic, however, we were new enough as a couple to still be very horny for each other. We went at each other with abandon, and it was actually a more passion filled night for us than the afternoon ashore. We fucked for a couple of hours in all positions, and Fran, like my Abby, really loved to end a session with me fucking her hard and deep from the rear. Her loud cries of climax must have been entertaining for the couples on either side of our cabin, and we laughed that our noise probably had initiated their own fucking - at least we hoped so. When I rejoined Abby in our cabin at 5 in the morning, we were still horny from the swapping experience, so we fucked. Then Abby gave me the details of what she and Ed had done, and it was so hot, I got a raging hear-on and fucked Abby one more time, then we finally fell asleep. We had breakfast with Fran and Ed in the upper deck cafeteria just before it ended at 10. We shared wives each of the remaining nights, but in the same cabin after having the stewards convert the beds from a single queen to two twins. It was a bit crowded sleeping two people in a twin bed, but a twin is certainly wide enough for fucking! And being able to watch one's wife being fucked by another man was so worth the bit of sleeping discomfort. We enjoyed our experience with them so much we exchanged contact information so we could get together if they ever came to England or we visited their area in the States.