To be in such a state of mind that you have no idea what is going on. Someone who is dumb as a box of rocks. A person who may think they are a thug and or a tough person however, they really are just plain stupid.
You can also consider this a look, someone who is out of the norm, ie, pierced like crazy or covered head to toe in tattoos.
Martin: hey man did you see that freak?
Johnson: yeah hes a dily rob
Howard: ugh dude, you are so dily rob