The subs are also quite bad. I actually think that I understand their Korean better than I do the subs. -_- Not really but with all the K-dramas I've watched, I better start to understand Korean soon. :p
I didn't understand why he almost let Yoon drown. Did he do it on purpose or is this something to do with the bullet in his head? I guess what confuses me most about this series is Moo-Hyuk himself. I'm never quite sure what he wants.
He doesn't want people to know about him.
I think that, he doesn't want people to grow attatched to him, and he doesn't want to be leaving anything behind.