N is for Nightwalkers! I can't say much about how these guys work into the novels, but I'll give some background.
Nightwalkers are descendants of the night goddess. They are NOT vampires, but they do not consume food like normal humans. They feed off of the energy of others. Think of them "drinking" in your aura and energy. The more powerful the emotion you're feeling, the better their feed. Some have preferences to what emotion they like best: fear, love, lust, pain, anger, sadness, etc.
The Nightwalkers have carved out their own "kingdom" in the Forests of Loretisium. This is a very small area in the central south of the continent, between the Merchant Coast and Torrhid, butted up against the Craul Mountains. It's a dark and old forest. And humans very rarely travel there if they can help it.