I'm thinking Joon bringing Dokja into the next scenario, when it's known it will kill him, satisfies the fate. If you know a person will likely die in some battle, and ask him to come with, or break him out so he can come, etc etc, then "you've 'killed' him", by letting him go to his death.
Also, I think Dokja 'loves' Joon the most, as he read a 3000+ chapter story centered around the dude, and that story was basically his only friend for years (aka, 'brothers in arms', closer than blood).