Blood memes

Why does the nurse need a red pen?

In case she has to draw blood.

A vampire walks into a bar and orders a cup of hot water. The bartender asks, "I thought you guys only drink blood?"

The vampire pulls out a used tampon and says, "I'm making tea."

My cousin died last week. He needed a blood transfusion, but we didn't know his blood type. He just kept saying, "B positive, B positive," but it's hard to be positive with him gone.