Rue's early life was complicated, to say the least. His mom still doesn't talk about it much, but he knows that she was raised in a Satanic cult and groomed to be the Devil's bride so she could carry the Antichrist to bring about the End of Days (which would be Rue). Rue has hazy memories of a dungeon and people in creepy robes, but he's not sure if it's a real memory, or something he imagined. 

While he was "christened" (or whatever the Devil-worshipping version is) as Ruination Morningstar, his legal name is Ruination Moore; his mother changed it when she escaped the cult with him when he was barely three years old. The ironic thing is that the cult thought she named him as a nod to his destiny as the Antichrist. Callie actually chose it as a middle finger to everyone who wanted to use her son as the starter of the apocalypse: she would raise him to ruin all their plans.

After they were free from the Satanists, Callie tried to raise Rue as normally as possible. She taught him to be a kind and caring person, though it was hard to deny who his father was; his powers started showing early on, and it made it very easy for the boy to get whatever he wanted from people. Callie made friends with people who could teach him control, as well as teach her how to protect him from those who would use him or hurt him. The Devil was his father, but he was always Callie's son.