
I'm pretty sure what this guy is would be classified as psychopathy. He seems to have a very small emotional range, difficulty distinguishing right from wrong, difficulty showing remorse or any kind of Empathy, and overall lack of any kind of genuine emotion. Note: psychopathy is by no means an inherently bad thing, and is actually quite common in authors/writers.

Eh in this case I don't think it's being romanticized. They don't outright say he has anything specific, and do show the real struggles and downsides to having these traits. They're not overdoing it, or making him out to be some crazy guy. Sometimes it's just fun to try and pinpoint or find a logical reason as to why someone would act or do the things that they do that very obviously don't fit the norm. Anything about any kind of diagnosis or mental disorders are really just headcanons made by fans and nothing to blame the author for.

This is actually the problem. The authors wants to make a character that's QuiRKy & WeiRD but they don't want to address that normal people don't really behave like that and that those behaviours actually implies a type of mental illness that is very real and extremely misunderstood in our society. So now ignorants ppl will real this and think "Wow that's so quirky and funny, I wish I can date someone like that", not knowing what those behaviours ACTUALLY implies. And then when they meet someone like that irl, they'll have false expectations towards those people, things like "I want my boyfriend to be extremely cold, uncaring, and aloof. But also extremely posessive and loving, and thoughtful, etc..."
And those dumbass won't even know how insanely unrealistic those expectations are... Do you understand my point? Misinformation can cause very ugly things. So I hate it when authors just try to make a character look quirky by making them autistic or smth, but then BOOM SURPRISE, right when they feel like it the character is suddenly self aware and mentally. That shit don't happen so easily in real life bro

If people are using Bl manhwa characters to determine what they want irl then I think that's their problem of not being able to distinguish or differentiate fiction from reality. Another thing to note is that people can have these traits and NOT have any kind of disorder. Nothing in this manhwa is promoting or trying to put a positive light on emotional disorders, and they definitely should not be trying to antagonize or make these traits seem like an evil thing. Like I said before, if people can't separate fictional preferences from their real life preferences then that is absolutely on them and not the author.
I don't have a problem with mental illnesses, autism, retardation, down syndrome, etc... Actually, I think it's GREAT to see such things depicted in mainstream media so people can be more aware of it. But the fact that some authors try to make certain characters look 'cute' or 'intriguing' by making them act autistic or retarded (even though said character is clearly not autistic/ etc) is just fucking gross bro. It's heavily unrealistic and flat out misinformation too, because these characters are clearly autistic at one point, then completely mentally healthy the next.
It creates a false image of what autism is, and therefore increasing misinformation about the topic. Now there's gonna be ignorant idiots reading this manga and thinking they want to be with someone who has a mental disability, romanticising the illness and having false expectations towards it. Where the fuck do you think those motherfuckers who fake autism come from? It's because they're dumb and then read shit like this.
Anyway, ik it's a long rant and I know nobody in this platform is ready to come to terms with this fact, but I had to get it out there....