Halloween Vampires

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?