I don't think that a NPD person would have that degree of insight into themselves that Lucifer shows.
I see Scrapheap as much more of a Narcissist Personality Disorder person than Lucifer. I don't believe that she is one at all.
I read all the chatlog that Scrapheap says is some sort of smoking gun.
She said:
vetivert says: what she gets wrong is to confuse "understanding" with "tolerant", "merciful", "sympathetic", "altruistic" and "kind hearted"
vetivert says: i am none of those
She has never made a secret of any of this, as far as I know. She can be kind to people sometimes, but she says that this does not make her a kind person.