This happened when I was 16, and 'Tim' was 17. I am now 18 and he is now 19.
I had a friend come over, lets call him 'Tim' and we talked about the regular, I had told him about this obsession I had developed with seeing anyone who would show me his penis. I had also told him I wanted to mutually masturbate several times. He wasn't whipping his penis out, but he didn't stomp the idea down right away either. So we talked and watched movies for a while and then looked at a few web sites with both male and female pictures and then went back to my room. We chatted about stupid stuff, who we wanted to 'do' me making most of it up, him, well I wasn't to sure about 'Tim's' stories being true, but he did have some good stories.
We made idol conversation avoiding the mutual masturbation that I was so eagerly hoping he would bring up. He didn't bring it up for a while but we did start talking about masturbating. That could have been enough for me, I wanted more but he was very open and honest about how hard he 'beat off' and how many times a day he did it, you know all the questions a couple of boys could come up with.
After he realized how horny I was from all that chatting, he randomly said, 'Hey you want to just beat off in front of each other?' I immediately said 'YEAH!'. He seemed happy to do it, and eager to take his cock out of his boxers. I found out for a good reason. Behind that thin layer of fabric, he was sporting a good half hard cock that was bulging his boxers out. I was hard as a rock and was worried he would be massive to my 7 inches; I knew I wasn't tiny, but I had imagined his cock so many times before that I expected a porn star or more.
He said I would have to put on the little porn I had and he would watch that and me and I could watch him as much as I wanted, we both grabbed socks off my very dirty floor and pulled our boxers down. Out of his boxers popped out a good 7-7.5' cock. He was now hard as a rock, I popped out my 7' cock and we briefly compared, I said I was impressed and he said he was impressed too at mine, he was much thicker that I was but we were both 'nice' in our own ways. We began stroking in our own ways, he held his beautiful member in his hands gliding up and down and rubbing the cut head on his stomach, he watched the porn mostly, as I watched him. He looked over and smiled several times. I was hopeful he would be okay with me at least putting his cock in my mouth. So right before I was about to pop I said last chance to get some of this, I said 'can I get some of that' when his head was huge and looking ready to burst, he said no not this time, and we both came. I came more than ever before, I launched a load up to my neck, then Tim saw me launch my load so he quickly came after me. He too launched a load onto his stomach, he told me he had beaten off while we were watching the movie so there was not a 'full load on board'. I wish I had seen him then but we finished up, and he went to sleep, I sat there for a while longer thinking about what had just happened and eventually beat my self off again thinking about the entire experience. We woke up the next morning and Tim and I talked, I didn't think Tim had enjoyed the entire event so I didn't mention it. He quickly once waking up said 'That was awesome!, I woke up earlier and beat my morning wood off thinking about it!'. I told him I would be more than happy to do it again later since my cock was now red and sore from a long night of work.
Tim and I have continued to mutually masturbate since then, he now has a very steady girlfriend, and a great sex life, I have a good girlfriend and we have a good sex life too. Tim and I have moved a little further into 'oral sex' but we still love a good jerk together. We love your site!