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!”