Kai hadn't ever looked this tired before. If Noah could describe Kai, he was not a guy who was easily comfortable around others. He was also careful and had clear boundaries with new people, keeping his distance and managing his personal space. He was likely an introvert, so it's likely that he only talked to people he felt comfortable with.
He's like a cat. He'll come to you if he's interested, and he'll back off if he's not.
When they first met, Kai also kept a certain distance from Noah. The man just came by to complain about not being allowed to go into the dungeon or to ask about Noah's missing during lunch.
After Noah returned from The Echoing Depths, he became more approachable. Noah himself noticed the change, but he still tried to sweet-talk him into letting him into the dungeon, though not as intensely as usual.
Kai's mood change was clear as day. The man was like an open book; anyone close to him could pick up on his mood.
