
A typical trope? I mean is this something new? I don't think its a bad attitude. His impression on Youngchan hits on lower level. He's a type of character that wants to go on his own pace but instead he was dragged by Youngchan's pace that's why the bickering never stops. "i just have a hard time tolerating anything out of ordinary."

I think it's a combination of his personality (he seems to be a super type A, overachieving workaholic) and trauma from the bullying in his previous department. The thing with being in a hostile environment for a long period of time is that once you're out of that place, the defense mechanisms you developed to survive, remain with you. So that could be why he's misinterpreting innocent interactions with Youngchan as attacks.
Can someone explain his bad attitude, I’d think since he’s so callous he wouldn’t hear the guy who constantly tries to injure him out while simultaneously cursing out the only guy who tolerates his attitude.