The bartender comes over and ask them what they want to drink
1st Vampire: Give me a shot of blood
2nd Vampire: I want a double shot
3rd Vampire: All I want is a cup of hot water

So the bartender goes and gets the drinks and comes back. He hands them the drinks, but looks kind of confused.

The bartender asked the 3rd vampire why didn't you order any blood the vampire pulls out a tampon and replies "I'm making tea".