
wow, you know nothing about narcissistic personality disorder and bipolar personality disorder, let me enlighten you. Narcissistic’s are often characterized as EGOTISTICAL, SELF-CENTERED, and MANIPULATIVE behaviour. Where in BPD some of the symptoms are: IMPULSIVE, SELF-DESTRUCTIVE behaviors.
In chapter 56 (I suggest you reread it again and observe like a responsible reader) Eunhan's thoughts tells us that he FELT GUILTY but he want to get rid of that feeling so he did what's SELF-DESTRUCTIVE, Right after that he puked right? Symptoms of TRAUMA, you can't really say that it was a narcissistic personality since that's so irrelevant to what's Eunhan's showing.
I'm not justifying what he did, Just enlightening you since you seem uneducated about disorders.
P.S. Not every thought's that are full of “I’s” are Narcissists, stop overusing that word to name a behaviour you don't like.

I don't think you fully understand his disorder either. Just because you ever work in field doesn't mean you're a master of it. I mean, look at how you try to 'educate' me. So much judgement and so wrong of that. Talk like immature brat who thinks they know and right for everything. I guess since your personality like that, you can find similarity to build reasons with rose tinted glass just to make excuse. You judge his character to fit your opinion.
What 'self-destructive' you talking about. Eunhan just being defensive there because he can't accept he is having a feeling for someone. He refuse when he's not in high above place. He must be adored and admired, not a mutual affection. Some chapters after this, Eunhan will have the inner thought that MC will come back to him because like many others, they can't resist him and can't help falling in love to him.
Well anyway, that doesn't matter because you already set value to that character ╮( ̄▽ ̄)╭
I don't want to waste anymore time with things like your opinion. With personality like yours, good luck with life.
he has multiple personalities, this isn't what he clearly want to do broooo, wtfffff, but hangyulll HE'S SO GOOD AT READING PEOPLE HE'S RIGHT BUT ML HAS SOME MENTAL ISSUES