FYI: Narcissism, contrary to popular notions, has nothing to do with loving or making love to oneself. As a clinical diagnosis the term refers to a disorder in which individuals experience a sense of having no inner, “real” self. Consequently, they tend to compensate for this by becoming especially charming, dressing stylishly, and otherwise presenting an attractive image to the world. This becomes pathological when they consistently avoid letting anyone get to know them well, fearing that anyone who gets close enough would then know what they themselves deeply feel, that there is no one there under the attractive surface.

Jacking off looking at a video of yourself (or looking in the mirror) seems to me a natural behavior for homosexually oriented men, one of the special perks of inhabiting a body that is of the type likely to inspire sexual desire in oneself.