The act of stealthily and creepily sneaking up on a female significant other or any female for that matter (if one is ultra weird and/or psychopathic) while she is in the shower and urninating on her. If this can be accomplished with the Psycho sound track playing in the background and in Norman Bates attire, the better.
"I totally hitchcocked the entire cheerleading team from the ventilation duct of the girl's locker room last Friday."
"Wow, that's pretty sweet, but speaking of, I hitchcocked your sister last weekend..and the weird part is I think she liked it."
"You Fucker, I'm so going to hitchcock all over your face!"
"Dude, you can't hitchcock another guy. That's just gay."