beta
I have reared this an insanely amount to notice some things.
One: Not only his hair but his eyes changed color.
Two: he makes it quite fast to point out there inside. Like he knows kwon won't like it.
Third: if you read carefully he sometimes looks like his talking in past tense.
So my theory it's that here ml is just a curse/demon made by the original sin or is part of it and has been hunting kwon so he is always alone so he can weasel his way into his life always.
What I meant by sin and from the little to no information we have.
Kwon was in a relationship aka marriage (sounds more like a sacrifice) and he wanted out so in an attempt of it he accidentally kill his husband and by the looks of it he gut hurt in turn like his neck was cut.