They're perceived as lacking souls, aren't they? And even if that isn't the case, if I had to guess I'd assume that reaction would serve to keep humanity from mating with things that it shouldn't - non-humans and corpses and the like. It's a visceral response to the point of being almost instinctive.
At the same time, not everyone experiences that to the same degree; I'm not afraid of them, though they definitely strike me as a bit strange.
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At the same time, not everyone experiences that to the same degree; I'm not afraid of them, though they definitely strike me as a bit strange.