Rakshasa
Rakshasas are shape-shifting demons in Hindu, Buddhist, Jain myth — fierce, cannibalistic, illusionists (maya). In Ramayana, antagonists (Ravana, Tataka, Maricha) ruling Lanka; some (Vibhishana) righteous. In Mahabharata, Bhima slays Hidimba, Bakasura, Kirmira; Ghatotkacha fights for Pandavas. Not 'guardians' — primarily malevolent disruptors of sacrifices, eaters of humans. Female: rakshasi.