Many are parasites. Some drink only blood to survive, while others include the nutrient-packed fluid as part of a balanced diet.
Just in case the post about the Vampyrella bacteria wasn’t enough for you… check these out. Not only do you harbor vampires in your home, they might be carried in by… your cat!
Dun, dun, dun! Some of these vampires are completely unexpected, –I mean, have you ever heard of a vampire frog? …Or a vampire squid? Weird, but totally cool, and not just bats, bats, blah blah, ticks, mosquitoes, derp. I love that a vampire frog is out there. Sort of. Actually… no. Now it’s creepy.