When I was 13 I had a step brother who was one year older.
We used to do all the boy stuff like football, cars and chicks but when our parents got cable we used to stay up late and watch the porn channels and sorta secretly rubbed ourselves under our blankets.
But week by week we slowly revealed our boners to each other until one day when we were camping we used to share a tent. He dared me to touch his cock for one minute and I said only if you do the same, he agreed.
I grabbed his cock and felt him tense up and then relax and after a minute of sitting there with no movement I let go and he grabbed mine. We went back and forth but every time we did it we would add a little something to it like playing with the foreskin (we were both uncut 7.5 inch) then rubbing and then playing with balls.
Finally it came to the stage where we would jack each other off until we blew. We both used to blow massive ropes onto our stomachs. We did this for sometime until one weekend we stopped.
Still to this day we still bring up in conversation how we used to jack off together, but we are never tempted to do it now.