Kwon on the Cliffside Cave stands for Ji-Yeon. The "Him" the kid tells Flocke and can't kill is Richard. I think the cave is MIB's not Jacob's. I think Hurley will end up being the protector of the island. I think we'll learn that Christian isn't the MIB in disguise, but rather a 3rd entity. And that the cabin was where he lived. Or possibly the cabin was once Richard's. Seemed like he needed to be protected from MIB.