Casper is an angel who was kicked out of heaven due to his terrible and unacceptable behavior. Before all of that happened, he lived with both his parents who eventually split up and Casper was left with his mother. Cas lived a somewhat normal life, his mother would drink from time to time and even smoke, thus making Casper curious and wanting to try out the things his mother would do.

Growing up, Casper always had a loose and rebellious attitude, he would never keep still during quiet time and always scream and yell around the other kids. This concerned his teachers a lot, they couldn't handle Cas's rebellious behavior and it was starting to get really out of hand.

Cas dropped out after middle school and was put to work at 15. Since he and his mother thought that there was no point in him continuing to study, a job would fit Cas more. Cas helped his mom out at her work by passing in boxes of beer and whine, thus starting his drinking addiction.

Years later, Cas began drinking constantly and getting himself into fights with other angels at bars and in the middle of the streets. His actions were then noticed by the higher class angels who serve God himself, he was dragged in by one of the angels and was put on trial.

After the trial, Casper was given the chance to be able to return to heaven if he can show that he's worthy and can improve his behavior, and to make sure that he's really owing up to his actions, they hired a demon businesswoman named Lucia to be his partner and work with her in the office down on earth, thus making the 2 into a dynamic duo.

Casper ends up developing some sort of a crush on Lucy, but due to her stubborn behavior, she's oblivious to Cas's feelings. Lucy heavily despises Casper for his loud and loose behavior, but she eventually gets used to it and later on softens up to him.