The first time I masturbated to orgasm was when I was fifteen. I am not circumcised and my foreskin was quite tight. We had an outhouse at the farm and after I did my business, I would pull the foreskin back from the head of my penis because it felt good.
One day, I became very stiff while doing this. As I pulled my foreskin back, a great feeling happened. My hips started to move uncontrollably, and the urge to thrust was very strong. I grabbed my penis very tight and the first load of semen shot out. It was very clear and thick. The next squirts were less in volume and had more white stuff in them. After I came, I nearly collapsed because of the good feeling.
Since then, masturbation has become a staple of my sex life including sharing everything with my partner. She demonstrates her techniques especially her first time, when she humped a pillow. Unlike the male (we get a dose of sleep hormones) she is energized and wants more. I try to come after she is completely finished and we cuddle to a mutual sleep.