Ikiryō

Ikiryō, or shōryō, seirei, ikisudama (生霊, lit. "living ghost," "eidolon"), in Japanese popular belief and fiction, refers to a spirit that leaves the body of a living person and subsequently haunts other people or places, sometimes across great distances. The term(s) are used in contrast to shiryō, which refers to the spirit of those who are already deceased.

The popular belief that the human spirit (or soul) can escape from the body has been around since early times, with eyewitness accounts and experiences (hauntings, possessions, out-of-body experience) reported in anecdotal and fictional writings. Vengeful spirits (怨霊, onryō^?) of the living are said to inflict curses (, tatari^?) upon the subject or subjects of their vengeance by means of transforming into their ikiryō form. It is believed that if a sufficient grudge is held, all or part of the perpetrator's soul leaves the body, appearing in front of the victim to harm or curse them, a concept not so dissimilar from the evil eye. The ikiryō has even made its way into Buddhist scriptures, where they are described as "living spirits" who, if angered, might bring about curses, even just before their death. Possession is another means by which the Ikiryō are commonly believed to be capable of inflicting harm, the possessed person thought to be unaware of this process. However, according to mythology, the ikiryō does not necessarily act out of spite or vengefulness, and stories are told of the ikiryō who bears no grudge, or poses no real threat. In recorded examples, the spirit sometimes takes possession of another person's body for motives other than vengeance, such as love and infatuation (for example the Matsutōya ghost below). A person's ikiryō may also leave the body (often very shortly before death) to manifest its presence around loved ones, friends and/or acquaintances.

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