Thanks for highlighting this mental illness, it's something to feel sympathy for, not to stigmatise. I understand that people with NPD can cause a lot of harm in interpersonal relationships, but it's the responsibility of everyone to be curious and educate themselves, rather than defer to the very lazy binary of 'good/evil'.

I actually find the concept of a person being either 'good' or 'evil' very childish - people are much more nuanced than that, even (especially) well-known people in history who have done very harmful things. We should judge the action, not the person.