Bob and Jim walk into a bar

Bob and Jim walk into a bar

"Hey Donkeyboy, get me a drink." The bartender gets him a drink.

Bob says, "Donkeyboy, get me another drink." The bartender gets him another drink.

Finally, Jim asks the bartender, "Why does he call you Donkeyboy?"

"I don't know. Hehaw-hehaw-he always calls me that."