I chose Doflamingo because it’s menacing and poetic, light and dark, beautiful and terrible. “Heavenly Demon” perfectly matches Doflamingo’s life from how he started in Marijoa to what he tried to accomplish. He was a Celestial Dragon/World Noble in the heavenly land then became a demon who ruled Dressrosa for ten years and had significant influence in the New World.

"Death god" is simply the biggest authority there is. You might not die from attacks of soldier, cannon, knight, king and even demon. But if death god decides, you go down to hell.

Dark king but Bohemian Knight is also kool

Doffy for sure