The Khasis are an ethnic community in Northeast India numbering about 1.2 million. The majority of them are Christian converts who belong to two main denominations, the Presbyterians and the Catholics. The Thlen tradition of the Khasis represents belief in a demonic spirit who is satiated with human blood and in return gives wealth and good fortune to his keepers. Narrated as a folktale, this traditional practice assumes significance when beliefs embedded in the narrative are enacted in the social discourse of the Khasis. This article examines belief performance; it explores how the Thlen belief and narrative is used to create social division and justify ostracism, murder, othering and demonization.