vampires walk into a bar.

Three vampires walk into a bar.
The waitress comes up to them and asks them what they'll have. ?
The first vampire says,
"I'll have a glass of O Positive."
The second vampire says, "I'll have a glass of AB Negative."
The third vampire says, "I'm the designated driver.
I'll just have a glass of plasma."
The waitress turns toward the bartender and yells,

"Gimme two bloods and one blood lite!"