Children of the Left and Right Hands.

Currently re-reading all of Castle once again just to remind myself of certain things.

On that note, the Left and Right Hand assassins? I assume one of them is Kim Shin, because that is exactly how the silhouette on the right looks like? What is it supposed to represent, are the opposing sides planned or 'fated' to kill each other? But yet again if they are all under Cheon Il-Do then it personally makes even less sense for that.