Ok, so started reading this after hearing a lot about it. I guess the H.P. Lovecraft style of horror with the mystery of not knowing or understanding what the antagonist is, is what this is going for.
So there are creatures that some people can see, but most can't. Maybe they're beautiful because Olivia said so. Some animals go mad but many don't. At least in Dean Koontz's "Innocence", they explain it. But the creatures can't talk, but appear and know they cause death and take actions to cause death. So there was suspense but nothing made sense.