A guy walks in to a bar with his pet monkey. He orders a drink and while he's drinking the monkey jumps all around the place. The monkey grabs some olives off the bar and eats them.

Then he grabs some sliced limes and eats them. Then he jumps on to the pool table, grabs one of the billiard balls, sticks it in his mouth, and to everyone's amazement, and somehow swallows it whole.
The bartender screams at the guy,
"Did you see what your monkey did?"

The guy says,
"No, what?"

"He just ate the cue ball off my pool table - whole!"

"Yeah, that doesn't surprise me,"

replied the guy.
"He eats everything in sight, the little bastard. Sorry. I'll pay for everything."

The man finishes his drink, pays his bill, pays for the stuff the monkey ate and leaves.

Two weeks later, he's in the bar again, and his pet monkey is with him.

He orders a drink and the monkey starts running around the bar again.

While the man is finishing his drink, the monkey finds a maraschino cherry on the bar.
He grabs it, sticks it up his ass, pulls it out and eats it.
The bartender is disgusted
"Did you see what your monkey did now?" he asks.

"No, what?" replied the guy.
"Well, he stuck a maraschino cherry up his ass, pulled it out and ate it!" said the bartender.

"Yeah, that doesn't surprise me," replied the guy.

"He still eats everything in sight but, ever since he swallowed that cue ball, he measures everything first."