We spent the whole week between Christmas and New Year's Day at Lena's house. Clothes other than bath robes were worn only for trips outside.

Other than restaurants, the only notable trip was to a sex shop where I bought Lena a second butt plug to match the one she gave Eve. The two women would wear them round the house together, a constant reminder of the next sex session they were preparing for.

After a few days of barely uninterrupted coitus, I was starting to remember stories about how the lionesses in a pride chose a male lion and demand that he shag them silly at every opportunity until he is totally worn out and they discard him for a new one. Eve and Lena were both insatiable like they were teenagers.

Eve admitted that she was starting to like anal. She still preferred pussy-fucking but asked for her ass to be serviced at least once every day. Rimming was a different matter, she didn't much like receiving and refused to consider giving. I wasn't going to press the matter.

* * * * *
After dinner before New Year's Eve I had had enough; the girls could play with each other if they liked but my cock was taking a 24 hour rest.

Lena had invited some neighbors to join her at a New Year's Eve party at a friend's house. She could have missed the party herself easily enough and would have cancelled the engagement but they had only just moved into the neighborhood and Lena did not want to start their relationship by bailing on them. Eve and myself were added to the guest list. We arranged to walk to Sue and Ian's house for drinks and take one car to the party.

"Wow, you look so good today," Sue exclaimed as she opened the door to Lena. "The holiday season seems to be having an effect."

It was true. Since Christmas, there had been a distinct change in Lena's mood. The hint of melancholy in her deep green eyes had been replaced by a sparkle. She was as quick as ever with a witty comeback but the familiar sardonic deadpan was now followed by laughter.

Eve knew the reason: Lena was happy again.

"Something like that," Lena replied to our hostess. She gave a huge grin as her eyes darted back in my direction.

"Oh, of course, your husband!" Sue exclaimed.

Lena quickly corrected the confusion.

"That's a pity, I really want to meet him."

"Well that would make one of us," the sardonic tone returned to Lena's voice.

Sue's mouth dropped open slightly as she realized Lena was planning a divorce.

Then the laughter returned to Lena's eyes, "Just don't tell anyone, he doesn't know yet.

In my experience infidelity is almost always a symptom rather than the cause of a marriage breaking up. People whose marriage has already collapsed often start screwing around before they admit the fact to themselves. Lena's marriage had for all practical purposes been dead for many years, she just didn't know it.

Early on I had assumed that Lena tolerated Bod's absences because she enjoyed the lifestyle his World Bank income allowed them to enjoy: the big house, the antique furniture, the luxury cars. Appearances can be deceptive, Lena came from money and the house belonged to her mother who preferred to spend time in her other residence in the warmer climate of Naples Florida. What is the point to keeping a spouse that does not provide financially, emotionally or physically?

Eve and I made small talk in the living room while Sue found an excuse to sequester Lena in the kitchen. After a while, Eve was called in to 'help'. This help seemed to take quite a while and Ian and I joked about what our wives were plotting in the kitchen. After what seemed an inordinate amount of time Eve returned with a tray of cups and Ian made an excuse to 'help' in the kitchen.

It was clear something was up.

"Honey," Eve began in a conspiratorial voice, "do you think Sue is hot?"

Of course I did. Sue was a Latina and curved in all the right places. In her mid 20's she had long black curls, ample breasts and a true bubble butt. Unlike a butt that is merely large, a genuine bubble butt is round like a globe, firm and eminently fuckable.

"I'd bang her," I whispered back.

"What about Ian?"

"No, not my type."

"If you were the type to go for guys."

If I was the type to go for guys, Ian would probably be the type of guy I would go for. Tall, muscular with piercing blue eyes. But I wasn't about to say that.

"He's OK I guess."

"They swing."

Lena had known this all along of course. This visit was her payback for the way that Eve and I had pushed her into adultery with us.

"You want to fuck him?"

Eve nodded.

"OK then, lets do it."

I could hardly refuse. For years Eve had tolerated or turned a blind eye to my infidelity. This was the first time she had asked for the same right in return.

My reluctance was not because I was the jealous type, but the thought that I might find out that I was the jealous type after things got started. How do you tell a guy to get his cock out of your own wife when you have just been ass banging his?

And ass-banging bubble butt Sue was all that I could think of since I met her.

* * * * * 
By mutual consent, the party was abandoned and we headed up to the master bedroom for a very different sort of party. We had a couch, a king sized bed, condoms, lube, two naked men and three naked women: More than enough for an excellent party and we had two bottles of champagne besides.

Sue and I started French kissing on the couch while Ian took my wife and Lena to the bed. This was slightly distracting at first; Ian went straight to work with his tongue between Eve's legs. I prefer a more leisurely approach. But I could afford to: I had one woman to service, he had two.

I stroked Sue's round butt as we kissed.

"You like my butt then," Sue stood up to present her but to me, bending over to show it at best effect.

"Love it," I replied running my hand over the firm fleshy globes and down her crack.

"I hope you will make full use of the opportunity then."

By way of confirmation, I pressed my index finger into her ass-hole. Sue gave a low, shuddering sigh of appreciation.

"Very full use."

Sue pushed her butt up against my face; Pressing my nose into her crack. I pushed my tongue into her asshole eliciting a gasp and "Oh yes, oh yes."

For the past week I had been making love slowly, gently. Caressing and teasing every part of Eve and Lena's bodies before reaching for my target. Now I wanted to go straight for her ass and cunt.

I continued riming Sue and pushed my thumb into her cunt. She was already completely wet. Perhaps there had been a little more than just talk going on in the kitchen earlier.

Sue gave a loud moan as I pushed my thumb downwards and found her G-spot.

Sue's knees buckled and I had to support her as she collapsed onto the couch. I pulled on a rubber and began shafting her pussy. Working her from behind so that I could see her butt to full advantage. Perhaps things were more even with Ian than I had assumed: he had two holes to fill and so did I.

With this change of position I could see Ian fucking Eve while she 69'ed Lena. I was somewhat pleased to find tmyself smiling at this: Seems I am not the jealous type after all.

Sue was enthusiastic, pushing herself back into my cock with each thrust. I squeezed my lubed thumb into her ass hole as I rode her. This was enough to make her start screaming with every thrust.

She was not yet properly prepared but I decided to go for broke. It was high time the bubble butt got rammed.

Sue was much looser than Eve but tight enough. I came quickly and fell sideways onto the couch. Sue followed me, keeping my cock planted inside her. This left me lying on my back with Sue on top of me.

When I was still trying to coax my wife into the deed, Eve had asked me how fucking a woman in the ass can make her come. It really isn't a secret. It's the same way many women come with a cock in their pussy: manual stimulation of the clitoris. The human anatomy is optimized for making babies. Making happy monkeys is a side effect, particularly the female ones. Some women have a clit that is perfectly positioned for vaginal stimulation, others get more stimulation from anal. But every woman I have slept with has had a clit that is perfectly positioned for my fingers when my prick is buried in her anus.

I frigged Sue with one hand and played with her nipples in the other. Over my shoulder I could see Ian fucking Lena on her back while Eve's hand worked underneath.

We had met Ian and Sue less than two hours. I had already fucked Sue in the front and back and Ian had fucked Eve and was working on Lena.

Sue's body was writhing and squirming under my hand, her ass grinding into my cock. Her cries became louder. Suddenly her back was arching and I felt her anus throbbing rhythmically, gripping my prick with each wave of orgasm.

Sue moved over to the bed and began playing with Eve's tits, kissing and caressing her nipples. They lay together on the bed, touching and licking intimate places. Eve was as fascinated by Sue's bubble butt as me.

Of all the unexpected changes in the past week, Eve's discovery of her interest in women pleased me the most. I have spent my life appreciating the female form in every way; It was now a pleasure we could share.

The pair started scissoring, moving their hips together in wide arcs. Then changed position to rub themselves together in the missionary position.

I decided adding a cock would improve this position and slid myself between the two slippery slits. Both girls signalled their appreciation and I tried fucking them both at the same time. Ian had the same idea and pressed his cock between their open mouths.

The position was intense but impractical. Each time my cock slid over the girl's clits, their hips would buck, pulling them apart. After a short time the foursome split into a pair of twosomes. We fucked each other's wives doggy style while Lena frigged their clits from underneath. Ian chose cunt again while I preferred ass.

By now the women were on a hair trigger and it didn't take much to make them come. We switched places and they came again. Ian and I took a little longer but it wasn't very long until we were all spent. Eve moaned appreciatively as Lena licked the milky fluid out of her ass. This was almost enough to give me another hard-on.

"It's almost midnight!" someone said. The New Year was welcomed with champagne and we talked about sex as we rested. Ian admitted that he was not fond of anal sex which seemed such a pity. Sue was like Lena: she actually preferred anal. When they first married, Sue had had to satisfy her anal craving discretely through ads on Craigslist. Then Ian had found out and there had been a row. After several weeks of argument they had visited a couples counsellor who had suggested they consider swinging.

"Anyone got any New Year's resolutions to share?" Sue asked.

"I have one," Lena replied, grabbing Ian's cock then as she grabbed mine as well, "or does this make two?"

We were both brought to attention by Lena's hands and mouth. Once we were both erect, Lena took both our cocks inside her mouth at once.

Ian lay on his back and Lena skewered herself onto his prick, cowgirl style. Ian's preference was fine with me: I would use the rear entrance.

Lena looked back at me and her eyes rolled up in their sockets as I slowly inched my cock into her ass. With her pussy filled, this was the tightest fuck I had ever known.

Moving was quite difficult. I started slowly. The experience was quite strange. I could feel my ball's touching those of another man at the end of each stroke and I could feel his prick inside her.

These inhibitions were quickly lost in the first few strokes. The look on Lena's face was satisfaction enough for me. Each thrust brought a new gasp, like she was having a small orgasm with each stroke. Lena told me later that this was not far from the truth.

Lena's back arched, her fingers dug savagely into Ian's arms and she gave a huge cry. This was enough to set me off as well.

When we were all done, I lay back on the bed and Eve massaged my wilted prick.

"Are you saying you want to be next?" I asked.

"No love," Eve replied, "I don't think I am quite ready for that today. There is something else I would like to do. Watch me."

Eve lay Sue face down on the bed and ran her hands all over her back, touching, caressing, massaging her friend. She lay down on top of her partner, massaging her back with her breasts and then her crotch drawing soft little sighs. Sue's legs were parted and a thumb worked into her cunt. This drew a deep gasp and a plea for more.

I wondered if my wife was planning to fist Sue, but she had another idea, one that surprised me.

Slowly, sensually, Eve bent down and kissed Sue's ass hole. The kiss was followed by licks and more kisses each bringing more sighs of contentment. Then at last, Eve pushed the tip of her tongue inside the woman's ass and tongue fucked her while her hand brought her to a thunderous orgasm.

* * * * *
Next morning when we returned to her house, the bombshell dropped. Lena came out of the bathroom with something in her hands, something small and white and plastic.

"I'm pregnant."