I was 16 at the time and my previous sexual experiences had been masturbating myself at least once a day for the past 3 years.
A friend was staying over for the night and my parents had gone out for dinner. I had gotten out of the shower and as I walked into my bedroom and there was my best friend with his pants around his ankles rubbing his penis. He looked a little embarressed but had said that he hoped I caught him. I sat beside him and started to play with myself. We layed on the bed and started kissing. We then moved around so we could suck each other. No one had come yet and he asked if I wanted him to fuck me up the arse. I was very horney and told him to take it slowly. He used a lot of lube and used his fingers first and then had his entire cock buried deep in my virgin arse. I was on all fours with my head on the bed. He fucked me hard for a few minutes before blowing his load deep into my arse. He then rolled me over and sucked me until I came in his mouth.
We waited for about 30 minutes and then started again. This time I fucked him and lasted a bit longer as it was our second time. His arse was so tight and I couldn't help but come inside him. I then sucked him dry tasting his come for the first time.
That was the first of many experiences we had together. We kept it going for about 5 years fucking at least once a week during that time.
No one has ever found out about what we did and even now we get together about once a month for a boys night out.