Board Thread:Off Topic/@comment-25396609-20171207232020/@comment-27425734-20180423000558

I think what you're trying to do is make him a "dark side" to him, but you need to explain why that dark side of his personality exists in the first place. Being good at killing people and showing no mercy are only traits of that dark side to him, but they do not justify its existence in the first place. You need to explain why he suddenly shifts from a charming pretty boy to a ruthless killer.

Presumably his background as being trained to being an assassin would explain that, but there's not enough detail outside of him receiving training from his parents and then going to Haven... for some reason or another.