Okay, here's my guess I think whatever he saw when he was a kid. It was like some type of vengeful spirit or like a mix of ghosts that got attached to yohan. And then killed him, split him in half. That's why there's a good spirit and vengeful spirit like yin yang
And then the mix of spirits takes over.seorim body. Just a guess idk
I love my pizza like I love my bl steamy and piping hot guys