It was the summer of 1988. I was twelve years old. The older kids in the neighborhood would always talk about "coming". We... the younger kids... kept asking what they were talking about and they'd laugh or tease because we didn't know.
Eventually one of them took pity on us and explained that when someone has an orgasm, there is white stuff that is called "come" and the orgasm is called "coming". That sort of helped, but we were really confounded by the idea of this white stuff. The older boys would very frequently talk about making women "come" and how you were only a real man if you could make a woman do that. We never really heard them talking about boys coming and we never had any white stuff come out of us when we had an orgasm, so we came to understand that coming was something only women did.
Now, in my back yard, we had a very large dog house... about 6' x 6' ... almost a small barn... attached to our garage in the back yard and sometimes I would sneak in there and lock the dog in the pen outside and masturbate. One day, I went back and did so just as I always did. I had my eyes closed and as I was reaching that point of orgasm something new happened... white gooey cum started oozing out of the end of me. I was horrified. I thought I had done something terribly wrong and I remember thinking it meant I was gay because only women did that... as though the biology would have been any different. Funny... it never occurred to me that I might be gay because I liked to play with and suck on other boy's penises. Or maybe I did subconsciously worry about that and this was the confirmation I had feared. I learned from older boys that you didn't want to be gay or want to do things with other boys. Those boys got beat up. So I was very concerned.
Eventually, I figured out it was perfectly normal for boys to cum. I was so relieved that there was nothing wrong with me. It's funny looking back, but honestly, at the time it really wasn't funny at all.