(Below is an old draft. Some details are now inaccurate to his current character. Will retype a more accurate description in time.)

Birthed by his mother with the purpose of being used as a weapon for the Lord of the Underworld, Cinnabar was a successful attempt at creating a being with an abundance of raw power. Cinnabar has expressed very little emotion in his life, as he simply lacked any and followed orders from his mother and siblings without complaint. 

Once, following said orders resulted in his sclera changing to a pitch black; the mark of a particularly heinous sin. He did not understand what he had done wrong, but regardless this change is permanent. While some demons hold those with black sclera with respect, others view them with fear or as a challenge, while those outside of the Underworld would generally view him in terror and disgust. This led Cinnabar to be even further isolated from others, and a feeling of loneliness began to develop in his later years once he was left to mostly fend for himself. He keeps up regular training and still obeys his mother, but is less inclined to listen to his siblings like he used to.

Everything changes when he meets an angel who claims to have recently fallen wandering the Underworld. Cinnabar's curiosity is piqued; he had never met an angel before and this was a rare opportunity to learn about them before the plan he was born for is executed. The angel introduces himself as Kardia, and unbeknownst to both of them, they were about to change each others lives forever.