It seems there might be a misunderstanding or confusion in the question. Narcissistic Personality Disorder (NPD) and Dissociative Identity Disorder (DID) are two distinct psychological conditions, and they are not typically associated with each other.
Narcissistic Personality Disorder (NPD): NPD is a personality disorder characterized by a pervasive pattern of grandiosity, a constant need for admiration, and a lack of empathy for others. People with NPD often have an inflated sense of self-importance, a preoccupation with fantasies of success, power, or beauty, and a tendency to exploit or manipulate others for their own gain. It is essential to remember that NPD is a personality disorder, not a multiple personality disorder.
Dissociative Identity Disorder (DID): DID, formerly known as Multiple Personality Disorder, is a complex dissociative disorder in which a person experiences two or more distinct identities or personality states that recurrently take control of their behavior. These distinct identities, known as "alters," may have their own distinct memories, behaviors, and mannerisms. The development of DID is often a result of severe childhood trauma as a way for the person to cope with overwhelming experiences.
It is crucial to understand that these are two separate psychological conditions, and there is no such thing as "narcissistic multiple personalities." While individuals with NPD may have difficulties with empathy and interpersonal relationships, this does not mean they have multiple personalities as seen in DID.
If you have concerns about someone's mental health or personality traits, it's best to encourage them to seek professional help from a qualified mental health professional who can provide a proper evaluation and diagnosis. Diagnosing and treating mental health conditions should be left to professionals with the appropriate expertise and training.