Another doodle of Rebel, courtesy of math class boredom! 

Rebel's backstory:

Rebel is a demon from the Underworld who was commanded by his uncle to terrorize and torment the humans of the mortal world.

One day, Rebel saved a human boy his age from drowning in a nearby lake following a motorcycle crash, feeling ashamed and guilty for "betraying" his kind, he left, for fear his uncle would exile him and see him as a traitor.

He took the boy he rescued with him, seeing as he felt killing him after so graciously saving his life would be wrong, and took the kid (who could no longer remember his name, only where he came from) to the cabin in the woods where he would later hide out.

Fixing up the injured kid and making him into a cyborg after he attained severe injuries due to the crash, after the boy revealed that he did not know his own name, Rebel says something that would change the kid's outlook on the situation, he said: "Well, this is a twist I didn't see coming," and so, the boy was now named Twist. 

Rebel took Twist under his wing (later on being quite literally after gaining his wings) and gave him the title of "Honorary Brother,"

Reb's real brother, Risky, would later show up after worrying sick about where his little bro disappeared to. Risky is quite shocked about his bro hanging around a mortal, but quickly accepts Twist as his own brother too.

Reb, Twist and Risky would later overthrow their uncle and destroy the kingdom of the Underworld, freeing the trapped souls of the humans, and banishing their uncle and Reb and Risk's cousin, Trouble, too.

The story still isn't over though, because Rebel ends up learning that the lab that Twist used to work for and therefore live at was the same lab that was trying to capture him in the beginning of the story, and that Twist's real name was Terri.

Twist ends up breaking in and saving Rebel, and the two of them stop the evil lab people

That's pretty much it... HOLY PARAGRAPH