You are one of the helpers of god and it's your responsibility to choose over angels who have committed different types of sins. You thought all sins were prettyharmless, until you met Nathaniel. He killed a lot of angels in a war between heaven and hell. He disobeyed god. He already lost part of his wings as a punishment for the sins he has committed and he will be in pain forever.

Nathaniel: "Tch, I don't understand why only I get punished. Everyone killed someone in that war!"