They also include an explanation for where demons come from. Demons are the departed spirits of dead Nephilim killed before and during the flood. They roam the earth harassing humans and seeking re-embodiment. In books of the Bible that follow Genesis, descendants of the Nephilim of Genesis 6:1–4 are called Anakim and Rephaim (Num. 13:32–33; Deut. 2:10–11). Some of these Rephaim show up in the underworld realm of the dead (Isa. 14:9–11) where the Serpent was cast down. New Testament writers would later call that place hell.
