The unnamed Ghost acts as the central antagonist of the urban legend and modern folk tale known as "Johnny, I Want My Liver Back" - though the titular Johnny also acts as a somewhat antagonistic force, whose selfish actions awaken a supernatural horror that exacts vengeance for his misdeeds: this style of horror would become very popular in series such as Tales from the Crypt and horror comics, in which unpleasant individuals received harsh punishment from beyond the grave.
History[]
The exact telling of the story alters dramatically depending on era and area, like all urban legends, however, it tends to focus on a boy called Johnny who is given money by his mother to buy liver, yet is a greedy individual and spends the money instead on candy for himself - Johnny then proceeds to steal the liver from a nearby graveyard to trick his mother and despite this obviously being an act of both grave defilement and cannibalism he eats this liver later on, along with his mother.
This causes a terrible fate to befall Johnny that night as a monstrous voice calls out, "Johnny, I want my liver back" - afraid but unable to do anything Johnny eventually admits that he ate the liver, to which the ghost manifests, rips out Johnny's liver and leaves.
See Also:
The Monster (The Big Toe) (a near-identical legend)