noun

a deviant person or thing.

killers, deviants, and those whose actions are beyond most human comprehension

nonconformist,eccentric,maverick,individualist,exception,outsider,misfit,fish out of water,square peg in a round hole,round peg in a square hole,oddball,odd fish,weirdo,weirdie,freak,bad boy,screwball,kook,wackadoo,wackadoodle