Re: Vampires: Fact or Fiction?
I know of no authoritative literature that addresses the topic of animation of a human body after death by an inhuman spirit. I will assume for now that it is not possible.
HOWEVER: there are many formulae in the collective Grimoires of these people that can reduce a victim's metabolism to the point of coma, etc. Then this person could be "Reborn" with an antidote and possibly be in a mind-controlled state (ala Psychic Driving) or subject to demonic oppression or even possession.
Fear of sunlight, etc., can be phobias induced by the oppressive spirits.
The drinking of blood after a terrifying death is a time-honored tradition in the Left-Hand Path and is done for the intoxicating effects of the victim's blood at the moment of death. They get high on the adrenaline and other endocrines in the blood.