In Hindu folklore, a demonic spirit that inhabits corpses and may be encountered by travelers is a vetala.
A vetala is a paranormal being associated with charnel grounds, cemeteries, and the dead. Rather than being permanently bound to one body, it can possess a corpse and leave it at will, using the reanimated body as a vehicle. Stories often portray the vetala as dangerous, but also intelligent, knowledgeable, and capable of prophecy or riddling speech.
Its most famous literary setting is the Vikram and Vetala cycle. A sorcerer orders King Vikramaditya to carry a corpse from a cremation ground. The vetala inhabiting it tells the king a story and asks a difficult question; when the king answers, the spirit returns to the tree, forcing the journey to begin again.
Vetala is sometimes treated as interchangeable with words such as preta, bhoot, or churel, but those labels describe different categories or regional traditions. The defining combination here is corpse possession, cemetery haunting, and the wandering frame tale.