Cheeky Monkey
A guy walks into a bar with a pet monkey.
He says to the barman "I'll have a pint of beer and a packet of peanuts please"
As the guy drinks his beer, the monkey jumps up on the bar, starts running around eating every thing in sight, then leaps onto the pool table and swallows the cue ball.
The barman shouts to the guy "HEY! if you can't keep that monkey under control, you can just leave by the way you came in"
The guy apologizes and offers to pay for everything then leaves.
About a week later the guy with the monkey returns to the bar, orders a pint and again the monkey jumps up on the bar, eats everything in sight, shoves a cocktail cherry up its ass pulls it out and swallows it.
The barman is disgusted and shouts "I'm not having any more of this, did you see what he did with that cherry"?
The guy says yeah, he still eats everything in sight but since that cue ball he now measures it first.