If you ever have a full sized article citing  appropriate verifiable sources (see WP:CITE and WP:SOURCE for advice) to put in the namespace please do so. But as long as the article remains a single paragraph stub for a protracted period, it is best to include it as a subsection of the relevant article like Acquired Situational Narcissism. In the case of Celebrity Narcissism which is unverified and totally devoid of citation it cannot be similarly included.