dog rock

A weathered, and typically hardened dog turd.
Usually ripe for kicking at or into anything you could imagine.

I spotted a old "dog rock" on the side of the road... So I soccer kicked that "curb nugget" right into the hood of some dudes drug rug.

Rock dog

To put it simple its another way to say a "boner" or "erection"

"Imagine buying a hinata body pillow just to get your Rock dog everyday."