At the time of the incident I am about to describe, my girlfriend, Carol, and I, Rob had been seeing each other for about a year.

We were both in our early forties and, in today's parlance, were 'fuck buddies' or 'friends with benefits'. Except that this was fifteen years ago and the terms hadn't been invented. We referred to ourselves as being in a 'fun' relationship. That is, we would meet up every couple of weeks and have fun.

It was a great arrangement. No strings, no jealousy. In fact, we had a lot of fun relating our escapades with other partners to each other and were both quite free in sharing our fantasies.

One thing I had especially noticed about Carol was how much she adored giving a blow job, and I mean she absolutely adored it. She would go at it for ages, putting in a lot of effort to cover every inch of my cock and balls with her tongue and lips, and always without fail would swallow my load.

We were discussing her love of giving head one evening, post-coital and fuelled by wine. I have to admit I do like to analyse why people enjoy what they enjoy. Particularly where sex is concerned. I tried to get her to explain what it was about sucking a guys cock that she enjoyed so much.

Was it the thought that he was getting a lot of pleasure and that she was providing that pleasure? She was very insistent that that was not the reason and that she actually physically enjoyed the feel of a cock in her mouth and especially the guy coming in her mouth and swallowing his load.

She really didn't understand why everyone didn't feel the same way about having a cock in their mouth. I commented that not all girls felt the same way.

"No, I mean women and men," she said.

I tried to put the counter-argument that most men weren't gay or bisexual so why would they enjoy it? She was adamant, and then she played the trump card.

"Well if you have never sucked a guy's cock, how can you tell whether it's a pleasurable thing to do or not?"

I had to admit defeat at that point and we moved on. But the discussion did stick in my mind. Why was she so evangelical about the intrinsic pleasure of sucking cocks?

It did start me thinking though. As I say I do tend to analyse things to death and I did sense in Carol a slight annoyance that I was not prepared to accept experimentation as much as she was.

I'm quite an adventurous guy and I wanted to show her that I like to experiment, so onto the contact sites I did go.

It was no surprise that it took very little time at all to find bi guys who were interested in meeting a male/female couple for a blow job. I honed my searching and came up with a shortlist of guys who seemed suitable. I contacted them all and after a bit of messaging, I arranged for one of the guys, Jeff, to visit us at my flat the next night that Carol was due to come over.

I decided not to tell Carol any details beforehand as I did want it to be a surprise. So she arrived at my flat as usual with no knowledge that we would have a third person joining us. We settled down with a glass of wine and I dropped the bombshell that I had arranged a special treat for us that evening and a third person would be joining us.

She was visibly excited. She'd had threesomes in the past and enjoyed them all. She immediately told me not to reveal the person's gender. She wanted to be that to be a surprise as well.

So the doorbell goes and I welcomed Jeff in. I introduced him to Carol who was obviously very pleased with my choice and couldn't stop grinning. We had a glass of wine to break the ice and had a jokey discussion about all and sundry, mostly sex-related. I was wondering how to progress matters when Carol left the room on the pretext of getting another bottle and returned stark naked. She declared to us both, "How do you like this then?"

Jeff and I both laughed and embraced the gorgeous Carol. I know how much she likes being naked with clothed guys and I could see it was turning her on greatly being sandwiched naked between two clothed men. Jeff and I were soon naked though and Carol was just as turned on by being sandwiched between two naked men.

She was positively wriggling with excitement as Jeff and I kissed and caressed her face and neck. I felt that it was up to me to direct proceedings in the direction of my aim. So after giving Carol a big wet kiss I said to her in a mock military voice, "On your knees girl and give our guest a proper welcome."

She laughed and said, "Yes, sir, captain," and sunk to her knees while saluting and making submarine diving noises.

Jeff had an attractive and fair size cock and it was standing nicely to attention. I knew Carol was going to enjoy sucking on it. She engulfed Jeff's cock with her mouth. Lips and tongue slobbering all over his helmet and down his shaft. I could tell they were both enjoying this greatly, so I introduced my cock into the action. I prodded it into Carols's cheek. She glanced up at me and smiled, she held a cock in each hand and started licking each in turn.

She brought our helmets together and really started to lick in earnest. It wasn't bothering me that my cock was touching another guys cock, in fact, I felt a sexy thrill at the touch and I stroked Carol's cheek to show I was ok with it. She had caught on to my plan at this point and started tugging me down by my cock, laughing all the time,

"Time for your lesson, mister," she commanded.

"Yes, ma'am, captain," I said and sank to my knees while saluting and making the same submarine noises that she had made.

Now she was in control and started to demonstrate how to give a great blow job. She made long licks with her tongue around Jeff's helmet, all the time holding my face close to hers. She took his cock out of her mouth and held it in her hand. Gently she proffered the helmet up to my mouth. I tentatively licked Jeff's helmet and underneath it which I know is ultra-sensitive.

He had both his hands on my head slowly guiding his cock into my mouth. In, then out, in, then out. Each thrust a little deeper. Carol was stroking my cheek with one hand and Jeff's buttocks with the other.

I started to do the things to Jeff that I like to be done to me when I'm getting blown. I had one hand on his buttocks pulling him towards my face and I held his balls with the other hand and rubbed a finger in a line between his anus and the back of his balls. I felt him enjoying that so redoubled my tongue and lip action on his helmet and cock.

I realised that I was really enjoying this now and fully understood and agreed with Carol's argument. I wanted this guy to come and I wanted to swallow his cum. It was not long arriving.

He gripped my head and pushed his cock further into my mouth. His hips started to shudder. He gave a grunt and his cum filled my mouth. I swallowed but then his next load followed and one more after that. I swallowed and swallowed. It took several to get it all down but I managed it. I didn't want to let his cock go and started licking and sucking his helmet.

Carol looked very victorious and whispered in my ear, "It feels fantastic doesn't it?"

I couldn't speak with my mouth still full of cock so I just smiled and nodded.

Jeff withdrew his prick from my mouth.

"You were absolutely right," I said, still with a gormless smile on my face.

Carol and I laughed and kissed and I hardly noticed Jeff dress and leave. He did manage an apologetic, "Sorry I have to go." as he left.

Carol immediately interrogated me about my feelings and what I thought. All I could say was that it was the most enjoyable and erotic act I had ever done and that I whole heartily agreed with her that sucking a nice cock is one of the most pleasurable experiences you can have.

So do you want to do it again?" she gushed.

"Oh definitely," I replied, "How about tomorrow?".

We laughed and cuddled and Carol gave me an expert blow job which, as usual, I enjoyed immensely, but it did beg the question.

"Which did I enjoy the most, being sucked or doing the sucking?"

All I can say is I have been enjoying both ever since and I still can't answer that question.

I certainly wouldn't like to do without either.