Ik-su is a priest who becomes crucial early on when Yona and Hak show up at his temple looking for shelter after fleeing the castle. He's the one who puts them on the path to finding the dragons—he basically tells them to seek out the legendary warriors and specifically directs them toward the white dragon first.
The guy's a total klutz. He's constantly tripping over himself and generally stumbling around, which undercuts the usual gravitas you'd expect from a priest. But he's genuinely kind-hearted, almost to a fault. He cares deeply about people, and when he can't help someone, it weighs on him heavily. It's part of why he ended up living in relative isolation with just Yun around—fewer people to feel helpless about. He taught Yun to craft and sell sandals as a way to survive without resorting to theft or robbery, trying to keep the kid on a better path.
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