It was Halloween and three vampires wen

It was Halloween and three  vampires went into a saloon and bellied up to the bar. "What will you have?" the bartender asked.  "I'll have a glass of blood," the first replied. "I'll have a glass of blood, too, please," said the second. "I'll have a glass of plasma," said the third.  "OK, let me get this straight," the bartender said. "That'll be two  bloods and a blood light?"