When I was in my teens I would always be so hard and horny when I woke up, not that that is unusual for men, that I would lay in bed and slowly wank, I still do now. I had already played with my hole when wanking and put things in it so knew how good it felt. So sometimes I would just blow over my chest but other times I would work my cock around until I could rub it against my arsehole. That felt so hot that eventually I worked out that I could move it around and get the head in my hole which solved the problem of the clean up because I would cum in my own hole. I loved it, but it took a few more years before I would let anyone else put their dick in me.
I wish I could still do it now!