This article suggests that narcissists know that they’re not liked by people who get to know them over time and that they don’t care. All they care about it getting what they want which is usually more status and money.
Whenever I was dazzled by a new narcissist who pretended they were offering whatever I was seeking, a tip about their true nature was that fear they give off. It was a sense that they knew the clock was ticking until I saw behind the mask. It always did work out that way in my experience.
It sounds like they’re vampires.