I suppose it's cause he kind of grows on you as the story progresses. It's interesting how Moondae keeps interacting with him even after the crazy things Cheongryeo did in the novel though he never does forgive him.
it's probably coming from the novel readers; they were hyping him up even before he appeared ╮(￣▽￣)╭
he's actually one of the best written and most tragic characters.. I really love him people give him a change (although the progression might be really slow lol)
he actually forgives him!! Moondae is an unreliable narrator so while what his thoughts might make it seem like he hates him, his actions tell otherwise. He never really hated him, just found him annoying and too mysterious and dangerous cause at the start he couldn't tell his next move. He's the first person who actually sees through him and comforts him, letting him find the meaning of his life, more than once eventually. I think their relationship is once of the most beautiful in the story but heavily misunderstood. Cheongryeo really cares about Moondae in the same way, you could say even more but the fact is that they don't really communicate properly sometimes and Moondae kinda is a tsundere, he doesn't even wanna admit that he was a VTIC fanboy lol. I'd stay for days weiting about them but I don't wanna give too many spoilers.
I mean, from what I read, I'm pretty sure he never explicitly says that he forgives him. I think he also said it in his thoughts. However, it is true that he has gotten used to having Cheongryeo around, especially his dog, and has a business-like but also amicable-ish relationship.
I honestly dont get the love for that vtic guy I hate him as much as Moondae does
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