Fault is a human-like creature that is created by Manifest to represent all of Manifest's mistake when he was a human. He was created in Solus, but his negative existence was rejected by the people. He was hated, and so, he lived alone until Manifest decided to abandoned him to Abyss. He was suffering there. But he managed to climb up to a world called Noir, a world of nothingness. Fault is in an adventure inside Noir to Solus to take revenge on Manifest and everyone who rejected him.