The big bathroom in my parent's house had a shower head that came off the wall. I remember seeing it off the hook a few times after my sister would shower.
One day, when I was 13, I flipped the switch that sent the water to it. The water came out harder and faster than the regular head I started to feel the water on my legs, arms, back, and head. When I put it over my penis, I felt a jolt. It felt good. I then sprayed the underside of my penis and it felt really good, and I started to get a hard on.
The more time I kept it on, the better it felt, and the harder my penis was. I then placed it back into the holder and stood under it whle playing with myself. I soon shot my cum all over the wall.
It was the most amazing feeling. A few years later when I was showering with a girlfrien,d I showed her what I did. She laughed and told me she does the same thing. We both masturbated together in the shower.