Psychic Vampirism is a form of vampirism in which the vampire needs to take in more energy than most non-vampires do. Though the exact cause of psychic vampirism is yet unknown, it is suspected that psychic vampires burn through energy too quickly, and then for whatever reason, cannot compensate easily themselves. For this reason, they need to feed on non-physical energy, such as chi, or prana. This can be done a number of ways, such as feeding from ambient energy (the energy given off in crowds at a concert, for example), or feeding directly from a group or individual.
The victim usually leaves the encounter feeling weak, tired and emotionally or physically drained. Depending upon the severity of the attack, it can take days to weeks or even months for the victim to fully recover. While there has been no reported cases of death caused by a psychic attack, one has to wonder if some of the unexplained deaths of otherwise healthy young people couldn't possibly be the result of psychic vampirism.