Dickbag

“NICE GOING, DICKBAG,” he yells at a miscreant in traffic.

“Dickbag?”

“…I was trying to go for dickhead, or douchebag, but it came out wrong.  I don’t even know what a dickbag is.”

“It’s what’s left over after you tell someone to eat a bag of dicks.  I mean, they don’t transport themselves.”