Shedim are a particularly dangerous lifeforms who are imprisoned on what the Archons and the Drazz describe as “The lowest Emination of the World-Tree”. No one knows what their ancient crime was, but they show a rare delight in death and destruction.
Shedim have no culture. The Shedim are individually locked in their own micro-plane alone for eons. Shedim hate the Archons with a special sort of vitriol
Shedim are PL 10-15 creatures. They tend to have powers like Hellfire Control, though they are as unique as the Archons who are their sworn enemies.
This would require some convincing. The Shedim are ancient beings of chaos and darkness. Its theoretically possible, but you’d need one hell of a good backstory.