A guy walks into a bar and orders twelve shots of the best whiskey in the house. The bartender proceeds to fill twelve shot glasses and stares , puzzled, at the guy as he begins to drink them down, one by one. As the guy is finishing the eleventh shot, the bartender asks, Whats the occasion?

The guy says,

Im celebrating my first blowjob!, as he finishes off the last shot.

Well, says the bartender, in that case, here have one on the house and he fills another shot glass.

No thanks, says the guy, If twelve didnt get the taste out of my mouth, one more wont!