A person who puts a turd on his sack right between the gnads and bends his nonerrect penis into it and fills his urethral with fecal matter. This can also be done with diarrheah.
Teen1: dude! Did you hear that guy in the bathroom!
Teen2: yeah! He was giving himself a choco cock.
Guy in bathroom: hey wanna join me!
Pretty much to have a poopdick, but a cooler, rhyming way of saying it. To be used when trying to be discrete about saying it, but who really needs to be discrete when talking about putting it in the butt.