Don't like the few ads but video good. Christian perspective from scripture below. Narcissism is from our old Adam nature, NPD is more like a demonic controlled person who has yielded their life to darkness. Very subtle in their maneuvering, you would think you were in the presence of a kind and loving person. Scapegoats know better.
Philippians 2:3 King James Version (KJV)
3 Let nothing be done through strife or vainglory; but in lowliness of mind let each esteem other better than themselves.