My step-brother and I fooled around together on a regular basis for six years, from when I was 13 to when I was 19. This was one of our many encounters.
It was late at night, and I had already gone to bed, but my step-brother was in the living room entertaining some friends who were sleeping over.
As I lay awake, he lightly knocked on my door, then opened it and whispered my name, as he usually did when it was time for some brotherly love.
I found this unusual because he had friends over, increasing the risk that our secret would be revealed, but I was as horny as he was, so I let him in.
As usual, he walked up to my bed in his gym shorts and T-shirt, and I moved my hand up his thigh and toward his rock hard, 6' cut cock, while I slipped my boxers down and he took my uncut 7' cock into his hand. We spent a few minutes just lightly caressing each other's dicks.
Normally, we'd do things I can't mention here, but this was an unusual occasion because his friends were there, so we had to be quick. I suggested he just drop his shorts and jerk off.
We'd already been messing around for several years, so strange as it might seem, I had never actually seen him jerk off before. I'm gay and comfortable with it, and while I'm sure he's at least slightly bisexual, I don't think he ever came to terms with it, so our encounters always happened with the lights off, and there were some things we didn't really do together. He always seemed to want to avoid creating an emotional connection between us, even though I wanted one; for example, at my request, we tried kissing once, and I know I enjoyed the feeling of lying naked in bed, caressing his hard cock with our tongues and lips locked together, but he stopped after less than a minute.
Anyway, getting back to the story, I watched in amazement, lightly fondling myself as he stood there holding his T-shirt up under his chin with his shorts on the floor, rapidly stroking his cock.
After a few minutes, his breathing became heavier, and he moved closer to me, his warm cum pouring over my chest. He quickly pulled his shorts back up and rejoined his friends in the living room.
I snuck across the hall to the bathroom and closed the door, spending a couple of minutes looking at my step-brother's semen on my chest. I put my finger into it and then touched it to my mouth. I had tasted his cum before, but I wanted to enjoy it before I wiped it off. After wiping it off, I went to the toilet and finished myself off as well, thinking about my step-brother's rock-hard dick.
I haven't discussed the things that happened between us with more than a tiny handful of people, but I've never felt guilty about it or felt that it was in any way morally wrong or unhealthy. In fact, I feel privileged that I got to have these kinds of encounters with my step-brother, someone I had known since early childhood and felt so close to. And to be honest, I still fantasize about him when I jerk off, even though we haven't done anything like this in nearly a decade.