The Fallen were believed to be rogue seraphim who were exiled to the human world.
In reality, however, the Fallen were a group of six Seraphs who were mapping the universe. They accidentally released the Cataclysm which followed them back to Meliz and destroyed their world. The six were able to warn the Seraphs in time to escape to Meliz's neighbouring world Eretz, and seal the veil between the two worlds. Two of the Seraphs, Dvira and Iaoth, turned back to face the Cataclysm and were devoured. The four remaining were then mutilated and had their wings cut off, before being thrown into different corners of Eretz's neighbouring world, Earth.