A little spoiler
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After Moondae's current abnormality removed, the truth revealed is related to Ryu Chungwoo's past (where he was in an accident causing his injury), which is actually related to Ryu Gunwoo's parents' death, and Moondae saw how was the situation when they died, resulting him being so sensitive towards Chungwoo and avoid him blatantly.
He blamed Chungwoo not out of actual malice, but out of an involuntary trauma response and misplaced envy that Chungwoo’s parents survived while his own didn't.

Oohhh so satisfying to finally see this part.
That means 'that' part is also getting near