Vampires

Okay so my concept of vampires is not super defined.  There are lots of different types of vampires in mythology.  There's the typical type of vampires that suck blood, and that would be the image most people have of vamires, but there's also supposed to vampires who suck emotions.  There's a keltic myth about a warrior named Scathatch who is supposed to be such a vampire, as well as having al martial arts have base in her style of fighting.  Then the 'traditional' or best known vampire made famous by Bram Stoker in Dracula.  They live in coffins, are repelled by garlic, can't come out in the light, or enter your house without permission.  There are countless myths of vampires, one originating with almost every culture it seems.  Then there's the fairly new concept of vampires created by Stephanie Meyer in Twilight.  This is my particular favorite.  

"If there is in this world a well-attested account, it is that of vampires.   Nothing is lacking: official reports, affidavits of well-known people, of surgeons, of priests, of magistrates: the judicial proof is most complete.  And with all that, who is there who believes in vampires?" -Rousseau

There are historical figures who were believed to be vampires such as Count Vlad who Dracula was based off of and drank the blood of his enemies.  Then there's the symptoms from diabetes which include receding gum lines making it look like the person has fangs, and the symptom can be temporarily relieved by drinking human blood.  xD  And then there are cults with people who call themselves vampires and drink blood, but they don't need to do this in order to survive.