Cannibals

Cannibals are monsters that feed on their own kind, it can also apply to members of a species that deviated from another and still preys on said species (for example a former human who preys on humans would still be a cannibal, despite technically mutating into a new species) : it is not applicable to predators from entirely different species (for example an extra-terrestrial alien that feeds on humans would not count).

Cannibals often cross-over with Man-Eaters (as many cannibalistic monsters will eat both their own kind and other species: some of the most famous cannibalistic monsters include the Wendigo and the modern version of the Ghoul.