Ikiryoh

A vampiric spirit from Japan, the ikiryoh has a most uncommon method of creation. It comes into being when a person has evil thoughts and bad feelings about another person for a long time. Eventually, these thoughts can gain enough power to become an entity and leave to possess the person its host hated (see ASTRAL VAMPIRE). Once it has done so, it begins to drain away his life-energy (see ENERGY VAMPIRE). An ikiryoh is exceptionally difficult to exorcise from a person. Rites involving the reading of Buddhist teachings are necessary.

Source: Maberry, Vampire Universe, 155