A guy walks into a bar with his pet monkey...
He sits down and orders a drink. While he's drinking the monkey starts jumping all over the place. The monkey picks up some olives off the bar and eats them. Then, he grabs some sliced limes and eats them too. As if that wasn't enough, he then jumps up onto the pool table, grabs the cue ball and swallows it whole!
The bartender shouts at the guy, "Did you see what your monkey just did?"
"No, what?"
"He just ate the cue ball off my pool table - and swallowed it whole!" says the bartender.
"Yeah, that doesn't surprise me," replies the man.
"He eats everything in sight, the little bastard. I'll pay for everything he eats, cue ball and all."
The patron finishes his drink, pays his tab and leaves.
Two weeks later, the same guy and his monkey are in the bar again. He orders a drink and, sure enough, the monkey starts running around the bar again.
The monkey happens upon a dish of maraschino cherries on the bar. So, he grabs a cherry, sticks it up his butt, pulls it out and eats it.
The completely disgusted bartender exclaims, "Did you see what your monkey just did?"
"No, what?" responds the monkey's owner.
"Man, your monkey just stuck a maraschino cherry up his butt, then pulled it out and ate it!"
"Yeah, that doesn't surprise me," replies the guy, "Ever since he ate that damned cue ball, he measures everything first."