why he's copying dongha anyways that's disgusting (╬￣皿￣)凸
I don't think they're brothers by blood. It's like, they're all the same (supernatural being) so they considered themselves as brothers.
Maybe the uncle is nursing superficial beings into his care or something the likes.
Like the anime Yamato Nedeshiko, the untie there take them (who were orphans) to her house to take care of them. So they're "brothers" but not by blood.
Because he wants their attention and he is mad because he thinks they abandoned and forgot about him.
I know they ain't just simping for their own brother rn (⊙…⊙ ) dongha bby get your ass back here before this turns into a incest manhwa