Compared to a lot of men/ boys I was a late starter in cumming, maybe 14 or 15 but I had got erections for years before, even at infant school. At high school a couple of my friends told me what I had to do to cum.
Previous to this when I was walking home from school one day I found part of a porno mag with a beautiful colour picture of a girl lying on her back spreading her labia wide open with both hands. I kept it and took it into the house in my school bag. I used to look at it regularly, wandering why she would spread her labia wide open like this but it gave me an erection easily.
The only private place in our house was the upstairs lavatory so one day after school I sat in there, looking at the picture and began to stroke my erect penis like the boys had told me.
Totally unaware of what was going to happen I just sat there playing with my erect penis and I felt some nice feelings, feelings getting nicer and nicer then eventually from deep within me came a volcanic eruption and all this cum erupted from my huge shiny bell end and went everywhere, all over my stomach and my legs and the carpet, maybe even a bit on the wall. I had a bit of a mess to clean up.
All my family were in the house, I cleaned up and wandered what had just happened to me. It took me a short while before I tried it again but once I did I cum into a tissue next time to save a massive clean up afterwards.
Eventually I moved onto cumming in the bath so that I could just let it fly everywhere then I started to go into the garden to do it and anywhere outdoors so I could just cum without using tissues and no clean up required afterwards.