It seems like he's lacking in fundamental knowledge that's usually gained in childhood. He's learning as he goes.
I see many with the theory that he was never a human to begin with, that he is a freak experiment of sorts. Which I think makes the most sense to why he's like that. I don't think he's necessarily a zombie or a Frankenstein's monster type... Like helloooo superhuman yet healthy blood circulation of a lethal concealed weapon ? Maybe he's a test subject used to find a cure which makes it so he was mentally "reborn" and has to re-learn everything again.
Oooh~ wonderful theory!
Ive spent the last couple of chapters tryna defend Guwon and all that but now Im like
Bitch I'm scared lmaooooo
All jokes of course. Im not scared but maybe disappointed I guess. Not necessarily cause Guwon is crazy, cause we knew from the start he's a bit insane, but just disappointed because he's looking like the boring and predictable kind of crazy right now. I guess we'll just have to wait and see how this story plays out.