There is a difference between the awkward, gauche person with poor social skills, and the Introverted Narcissist who Can’t Do Better.
Imagine you are at University, sharing a dorm room with such a person. (I’m naming the person ‘Jade’).
You assume she comes from no where, had no upbringing, no money, because of the way she behaves.
Yet, Jade claims she is ‘uptown’ (coming from a rich family), despite having the manners and presentation of a hog.
Jade brags about everything with not only no proof, but with the opposite evidence. This is constant.
Jade tells you she is going on tonight. You are sitting over there, studying.
Jade never leaves the room, never makes a call or receives one.When you are ready for sleep you see her sprawled on the bed snoring.A normal person who had made an announcement about going out would explain why their plans had changed.
Jade says nothing because in her twisted mind what she says to you is akin to talking to a plastic fork.
If you should say, “I thought you were going out…” her answer will be a sharp; “How is that your business?”