Throughout the book, Snow is seen repeatedly trying to manipulate other characters, such as him appearing to fake friendship with Sejanus Plinth (and his unsuccessful attempt to manipulate Plinth for money at their first encounter). Later, he convinces Clemensia to forgive him; the books make it clear that he's not being entirely honest with her, but it's unclear whether he's actually trying to gaslight her or just being manipulative.
He's also rather horrified by being treated as "normal" or "ordinary" and expects special treatment.
These attributes are highly characteristic of narcissists. That being said, was Suzanne Collins consciously presenting him as a narcissist (or at least having narcissistic tendencies)?