we never get any explanation about the main character. we never find out where he came from, we never find out what he is, we never find out what his motivations are, we never find out what his purpose in life is, we never find out why he kills people. if we don't know anything deep about a main character in a movie then we can't feel any sympathy for them and we can't care about them and the movie fails because of this.
sharewhere he came from: Kryptons evil sister planet
what his motivations are: ever raised a 10yo?
It seemed pretty clear to me he was the offspring of a demon from Hell who had his own freewill til the demon that came in his spaceship poesssessed him.
I myself didn't like the ending. I wish it ended with Tori killing him. Then again with the demon still inside him it would come out of him then possess Tori and then possess other people til it possesses someone at a nuclear bomb facility to destroy the world.
So, I guess now having thought all that the world is doomed regardless.