I had ended up sharing a flat with a workmate. Originally there had been three of us in there, though one had moved out. As it was only a two bedroomed flat, I'd converted the living room into a bedsit arrangement for myself.

Me and the remaining guy would sit in my room and watch TV. It was most comfortably done from my single bed, and since it wasn't a very warm flat and we didn't have a whole lot of cash to spend on heating, we'd often get under the duvet together, both wearing bath robes and definitely no funny business. As far as the relationship went, we were both straight and just friends.

Then one night, I'm not sure quite how it happened, though a few drinks were involved, I must have offered him a massage and he must have accepted. We'd never done anything like this before, but suddenly I had him face down on my bed, naked apart from a pair of red briefs and was giving him a good back rub. I was still wearing my bath robe, with nothing underneath as usual.

As I worked down his back, I started to rub his butt cheeks. The briefs were getting in the way, so I progressively worked them lower and lower until his buttocks were fully exposed. Then, without asking, I quickly whipped them off so that I could rub down from his buttocks and onto his legs. He squirmed in surprise as I did it, but he didn't seem to mind.

At this point, I was sitting cross-legged beside him, and I felt his hand start to stroke my leg. While it was pretty obvious with hindsight, there was still no admission from either side that this was in any way sexual. I was becoming concerned that, as his hand rubbed up and down my leg, it was slowly progressing further up the leg and there was a danger that his arm would rub against my cock. This was, by now, a full scale erection and was definitely going to give the game away if he touched it.

Sure enough, as he rubbed my leg, his arm brushed against my erection. I thought that might be an end to the whole thing there and then, but he stroked down and back up once more, as if to double check what he'd already discovered. Suddenly his hand wasn't on my leg, it was around my cock and gently pulling on it.

Still stroking my cock, he turned on his side to reveal his own erection, which I began to stroke too. After a minute or so of this, I went to reposition myself to go down on him, but he shot his load before I could get my mouth around his cock.

And that was an end to it. With his sex drive satisfied, he was now disgusted with what we'd just done. He went back to his room, leaving me unsatisfied and having to sleep in the wet patch. He nearly moved out the following day, but I persuaded him to stay on the understanding that nothing like it would ever happen again. I did test the water a couple of times after that, but he wasn't interested.