The lamiae have different names and images to cover their own insidious nature. Harper Paget knows this because they have been enemies of Harper's family for generations . . . even centuries. One of his ancestors was even executed as a witch because of the influence of the lamiae. Harper encountered them in China under the names of kuntilanaks and le-aks, Indonesian creatures who caused the death of a Canadian colleague and almost causes his own when he is attacked while confined to a wheelchair.
Back in the USA, he is startled to learn that one or more of them has followed him even to a mental health wing of a hospital in Atlanta, Georgia. His brother who is a patient in another hospital encounters one of them and almost loses his life. Harper tells a Nurse Practioner to beware of who she might encounter in the halls of the hospital where he is staying because they can be doppelgangers (which is German for 'double-walkers') who can look like him or others. She, it turns out, is in love with Harper, which puts her in even graver danger