He literally can fit under the medical term "narcissist". Narcissists do not believe they need help so they don't ever seek it. They even refuse it. People need to acknowledge that they can be the sickest people ever. Causing harm to others and themselves, but never being able to actually change nor seek help.
I dont think he fits for the term narcissist solely . He does give off bpd vibes - so it can also be bpd with narcissistic traits. But obviously i cannot just diagnose him - based on just the chapters i have read till mow . But he definitely isn’t just fully narcissistic . With how his character has been shown , he can go to therapy if someone guides him. Or tells him in his way- how it can benefit him.
And also to support the reason why i feel he is more towards bpd than npd - is bcz they cycles of guilt and on top of that THE BLANK FEELING , that he feels a lot of time , that why he used to lose interest fast . AND THEN THE OBSESSION … and also his childhood of abandonment is also something that can indicate him developing borderline personality disorder. Maybe thats why the name is ‘borderline of delusion’ bcz he has both borderline traits and is delusional!? ?
Everyone is saying he should go to therapy even I think the same but with your mind this messed up you really won't think straight that is why you need at least one person to guide you. I haven't read much bls where the character gets therapy but I've read one and even in that the mc was alone but he still had ml with him to guide him to get therapy. I'm not saying nanjo should be there but if at least one person stays with him and guide him he'll get through this eventually.