A few years ago, when I was in my mid thirties, I was single and living in London with a good job and a good standard of living.  I used to go clubbing every saturday night with my flat-mate and best friend, who happened to be gay.

I have always been open minded and had no problem with Andrew's lifestyle.  Even when I sometimes walked in on him and a partner, I simply appologised and closed the door. I was able to acknowledge that he was young looking, slim and handsome, but I certainly didn't find him sexy.

One sunday lunchtime, after sleeping off the effects of the night before, I was lying on the bed, naked and idly masturbating without a thought in my head, when Andrew walked in with a cup of tea.  I didn't bother covering up as we had seen each other naked many times and never worried about it, but this time, for some reason and to this day I couldn't say why, I didn't stop.  I kept on slowly and absent mindedly stroking my cock.

Andrew put down the cup and sat next to me on the bed.  He watched for a minute and then reached out and moved my hand away, to replace it with his own.  It was like I was in a daze, I simply let him do it.  After a while I relaxed and realised that it felt good.  Well why shouldn't it?  I liked women doing it and a hand is a hand I said to myself.  I closed my eyes and lay back to enjoy the experience.

Then, I felt his tongue lick my exposed cock head and his lips slide over it.  My eyes flew open and I was about to stop him, but it felt great.  I watched as he sucked me and I only stopped him when I was about to cum.  Andrew stood up and quickly undressed.  He lay next to me and asked me to do it to him.  You must remember that I had never been gay or even bisexual but I didn't hesitate.  I bent down, opened my mouh and took his cock inside. and I loved the feeling and taste.

We lay together for ages sucking and touching, then he asked me to fuck him.  At this I did hesitate.  After all, I wasn't gay.  But I was so turned on.  For some reason I didn't want him to go on all fours.  It seems silly now but the idea was just too gay.  I told him to lie on his back and I lifted his legs over my shoulders as I had done with many women.  I eased forward and held my cock, rubbing it against his anus.  He asked me to use some lubricant and there was a moment of scrambling as I found some, then I moved into the same place again and poured a little oil on him, working it around with my cock.  He was moaning softly and almost begging me to do it.

Half an hour before I was straight and now I pushed forward, my cock easing into him, sliding past his tight anus to move deeper inside his ass.  I moved inwards slowly until my balls were against him and the whole of my 8" cock was buried in another man's ass.

I began to move back and forth, loving the heat and tightness but most of all loving the feeling of forbidden fruit, that I was actually fucking a man.  I listened to Andrew moan, felt him squeeze my cock and rise up to meet my thrusts, reached down to wank his cock and finally I lost control. I was ramming hard into him now, really pounding him as he moaned and cried out.  It was all too much.

I felt my orgasm approaching and I slammed hard and deep into him.  Forget safe sex, forget straight, forget any thought of caution, I was a wild animal.  I lay forward, pushing his knees to his chest as I worked my hips to almost savagely fuck him.  I came with a roar, exploding deep inside his ass with one final mighty thrust and Andrew screamed with me.  I held him there as my cock pumped again and again, filling him with my cum until I had nothing left to give.

I fell back and Andrew turned around to lie with me.  He stroked my chest and told me how wonderful it was and I began to come back down to earth.  Only to experience a feeling of guilt.  Not guilt that I had fucked another man, but guilt that I hadn't thought about his pleasure.  I don't remember any thoughts of wonder about what we had done and how it fit my straight self image but I do remember turning around to take Andrew's cock in my mouth and I do remember sucking him and wanking him until he came in my mouth as I drank down every last drop.

So that was it.  From straight to out of control bisexual in one quick session.  I have never regretted it and I now have fun with both sexes, although I still tend to be a top rather than a bottom and I'm still dominant in any situation.