A vampire is any creature that consumes another's life force in order to supplement and extend their own. They usually start out as a regular person with great desire for power or immortality, before coming upon some magical method they choose to pursue for these ends; this may resemble classic draculas, something more akin to a lich, or something entirely different. Many also believe them to be a fairytale.
Vampires typically appear somewhat desaturated and lifeless, as the extension of their life comes at a cost to the vibrancy of it, and disrupts the natural order of things such as connection to the Residuum. The exception to this is while they are feeding.
Prior to the Panic, there was some degree of vampire high society in the classic traditions of much vampire fiction, presumably skewing towards vampires who leaned towards those aesthetics. Darling Malice's killing of Virtue Mondegreen was the beginning of the end of this scene.