Pissurbate
When s/o masturbates while peeing.

It could be done to please someone's eyes, or for the sole purpose that the feeling is awesome. It is simplier to do for women, and they usually find it awesome if not too disgusted to try.
Once I caught my girlfriend pissurbating in my bathroom and I almost jizzed my pants.

Once a girl told me: "I like to masturbate when I'm home alone, but, if I have a full bladder, I'd rather pissurbate, it's much more fun!"