Fear and repugnance intermixed.  A feeling which perceives not just a threat but a quality of intense wrongness or perversity about the threat, yielding a sense of evil.  As a genre, Lovecraft called supernatural  horror “the literature of cosmic fear.” and said that  “no better evidence of its tenacious vigour can be cited than the impulse which now and then drives writers of totally opposite leanings to try their hands at it… as if to discharge from their minds certain phantasmal shapes which would otherwise haunt them.”