Diane had given me my ultimate birthday present, and I felt compelled to at least try to reciprocate, but to do so would take me far out of my comfort zone.

Before describing this adventure, I need to give a little background. I had temporarily left my wife to shack up with Diane. The motivation was pure sex, and though I loved my wife and family, I could not resist fully exploring this relationship. I probably did not need to move in with Diane, but I did, and very much regret doing so. I had convinced myself that moving in with her, for a short time, was just like going off on a skiing holiday with some mates; a short self-indulgence.

Diane decided that we should take a new apartment, and as we moved in, two guys, Jim and Allan, helped us. They lived in the apartment next to ours, were Diane's age, and were both accountants and members of the same surf and squash clubs. In almost no time at all, they helped plan and carry-out Diane's exhibitionist episodes, which made quite a bond between the four of us.

Jim was a homosexual, Allan enjoyed sex with either gender. Neither were in a relationship, but enjoyed "playing the field". Allan worked near my office, which was close to a rail station, from which Jim could commute the short distance to his office. So, along with Diane, I drove them to work almost every day.

Now to Diane's fantasy. Put simply and crudely, while I was fucking her, she wanted me to be fucked from behind. It never worried me, as I was sure it would never happen. But now it needed careful consideration, and I admit I was appalled at the prospect. After all, I was entirely heterosexual and had never had the slightest impulse to be otherwise. But I'd started to live with Diane for no other reason but to experience the full range of sexual exploits that she'd opened for me. She had delivered, and now she demanded that I deliver.

Diane planned everything with Jim and Allan assisting but no discussion involving me. She invited both to dinner one evening, Diane wore her most alluring and revealing dress. We all enjoyed the meal she had prepared and served, together with a fair amount of wine. When we had finished coffee, she told us that our adventure was to begin. We three guys were to strip down completely. I felt humiliated, being at least ten years older than the others, and being a lot higher in the business world than them.

"Take hold of Jim's penis," Diane ordered me. "I want you to get it nice and hard."

Reluctantly, and gingerly, I obeyed, while avoiding Jim's gaze. "Now get Allan ready."

While still feeling somewhat reluctant, it shocked me to realise that, not only did I enjoy the feel of each penis, I had become erect. A penis is a wondrous thing. We enjoy the feeling of our own, and the feel of other penises was becoming equally enjoyable.

"Now rub your penis against Jim's. That's it. Now hold both his and yours together, and rub them both. That's good. Allan, can you join in? Good. It looks like your cocks are friends with each other. Beautiful."

Diane moved around us, clearly enjoying the spectacle that she was creating. After a little while, she told me to kneel and take Jim's cock into my mouth. I stood there, not believing she was serious.

"Come on, you can do it. You'll enjoy it," she encouraged.

I must admit, it had been a fantasy of mine to take my own cock into my mouth. I had tried but was not able. Probably just as well, as it may have become an obsession. Anyway, I knelt and took Jim's juicy cock into my mouth.

The sensation was wonderful.

"Now you know why I love gobbling yours. Let him feel your teeth. Good. Allan, would you like to join in? Can you take both at once? Nearly. Rub your tongue over them. Lovely."

I had not noticed that Diane had taken off her dress. She now led me by the cock into the bedroom, followed by the others, and told me to lie across the bed. She then lay on top of me, in the sixty-nine position, and took my cock into her mouth, as I explored her wet pussy with my mouth and tongue. Another cock joined mine, competing for Diane's attention in her mouth. Then, right beside my head, another cock slid into Diane's pussy, rubbing against my tongue.

Who came first? Probably me, but the first started the others, and very soon I felt cum flowing onto my groin and tasted it in my mouth. It was hard for me to believe what was happening, and I do admit that my recollection is a little blurred. We lay quietly next to each other, across the bed, and I must have slept a little. Eventually, I was woken and Diane took me into the shower, before returning to the bed. Jim and Allan had already showered.

"Get yourselves ready," Diane ordered, as she climbed onto the bed, on all fours. I could smell her readiness, and, now hard enough, I took her from behind. Someone's cock was gently trying to enter my virgin hole, but with no success, and my own erection deflated. It clearly was not working.

"Let's try this another way."

The next few minutes were spent lubricating my anus, fingering it, relaxing it, and generally making it more amenable. I knelt on the bed, and slowly, gently and carefully, Jim's cock found its way into its target while Diane got my erection back. She then knelt before me on the bed, and carefully eased her way back onto my cock, guiding it to its home. It took some time to get into a rhythm, assisted by Allan who, when our trio was finally working effectively, made it a foursome by fucking my mouth and Diane's, in turn.

Diane had made her fantasy a reality. I guess this satisfied her. I had found it cumbersome, and very much contrived. I enjoyed the earlier episode, before my little nap, much more. I derived no physical pleasure from having a cock inside me, but the mental satisfaction was undeniable. The indignity of being "prepared" for penetration, the abandonment of exposing my anus to be used, my submission to so many new experiences, all made me wallow in delicious vulnerability.

I had learned that someone else's cock felt and tasted wonderful. I could envy girls in this regard. This had, surprisingly, provided both physical and mental enjoyment. I could understand why Jim and Allan enjoyed such homosexuality. I felt more in tune with Allan, who enjoyed both genders, purely for the promiscuity. I could not understand how Jim derived pleasure from invading a guy's anus. For my part, being fucked made no sense at all unless there was an audience, and my indignity witnessed. Then it would be the ultimate act of submission. I don't think I could fuck another guy - no submissiveness in that!

At the time I could not understand exactly what kind of pleasure Diane had derived. Months later I was helped to understand. She had become a domme, achieving great satisfaction by reducing me, her manager's manager's manager, to being a helpless submissive slave to her every salacious whim.

She had the power sexually. I had the power at work.