Satan (サタン Satan?) Formerly known as Lucifer was an fallen Archangel who fell from grace when he defied God by siding with the demon race after he learned of God's plan to wipe them out. After their seeming defeat in Cretaceous era Earth, Satan and the army of demons went into hibernation, frozen in ice caps across the world. They remain in this state until they wake up two million years later, to discover that the Earth had been taken over by humans. Disgusted by these new creatures, Satan decides to deal with them first before resuming his battle with God.
As part of Satan's plan, demon general Psycho Jenny wipes Satan's memories and replaces them with those of the recently deceased Ryo Asuka in order to infiltrate human society and find their weakness. While living as Ryo, he befriends the timid human boy Akira Fudo, who becomes his best friend and, as Devilman, his greatest foe. Satan ultimately wins his war against humanity, but comes to regret his actions after unknowingly killing Akira during their final battle, before the world is attacked by God's angels
