A drunk stumbles into a bar, and staggers over to a young man sitting alone at a table, and looks down at him with a leer, telling him,
"Hey! You! You know your mother is fat, don'tcha?! And ug-ugly! *Hic!!*"
The young man ignores him, so the drunk staggers over to the bar and orders three shots of whiskey. After he finishes his drinks, he staggers back to the young man and tells him,
"Your old lady may be fat and ugly, but I'm still gonna have sex with her! Nasty, nasty sex!"
Again, the young man ignores him, and continues to drink his drink.
The drunk leaves and comes back an hour later, and heads right for the young man.
"Hey! So I just had sex with your fat, ugly mother...three times! Ya shoulda heard her moanin' and squealin'! Howya like them apples, boy?!"
The young man ignores him.
Then the drunk shouts, "And now I''m goin' back for more and we're gonna--"
The young man interrupts him and says, "You're drunk, Dad. Go home."