Chagrin

There is a global belief in Luctus that every evil, nefarious act and every bad thought stems from the same source. When a creature is corrupted or a village is attacked, there is an understood agreement that an unseen force called Chagrin moved that creature. When a man thinks about cheating on his wife or stealing bread, it is because Chagrin is corrupting his mind.
While this is an unseen and unobservable force, there are records in history of Chagrin Spawns, creatures made entirely of this corruption. However those are rare and the ones that beat them even more so.
Maniacs, murderers, insane people, evil outsiders and step-mothers sometimes believe that Chagrin is not a mystical force motivating evil force. They believe it is their true nature as mortals attempting to manifest into their actions. 
These people, scum, the worst of the worst, act only in impurity in order to honor these “bad thoughts” that they believe emanate from their very essence and usually end up committing indescribable atrocities in the pursuit of this corrupted nature they believe in.