Giuwon's origins

I honestly believe that Guwon is an experiment, he has the eyes of the worms/zombies. At the beginning it is said that some were actually hopeful to get immortality, and Guwon crawled out of a collapsed building, so it is likely he's a human experiment with some ADN enhancements of the zombies. And as such, he really has no complete understanding of human behaviour, socialibility, etc, hence why he kills what he perceives to be detrimental to his cause.