This actually happened when I was 15
Alfie was one of my friends in secondary school, he was of medium height fairly tanned and was a little stocky.
The first time we done anything was at school in the toilet, he had a hardon while pissing and being a bit of a typical guy he felt the need to mention it, at that point I got one to, and we both masturbated in front of each other.
Then once we decided to meet up after school, so at 3:30 we both met at his house (fairly close to the school)
He started by touching my crotch, feeling my boner, I did the same to him and with in no time we both had our dicks out and were wanking, we were looking at each others dicks in fascination his was around 6.5 inches with a bit of girth while mine was less girthy but longer.
He suggested we do each other so I reached over and took his dick in my hand and he did the same to me, it was good.
After a while we both began to breathe heavier and. As he went faster so did I, and in the end we both came in unison, him coming all over my hand while I pumped him dry and he did the same to me, after that we stood there holding each others still hard dicks while talking about what we just did.
It wasn't our only encounter.