Carmilla, an Assassin-class Servant, emerges from the shadowed legacy of Elizabeth Báthory, crystallizing her vampiric transformation into a figure stripped of youthful naivety. She embodies the infamous "Blood Countess" mythos, her legend steeped in the macabre ritual of bathing in virginal blood to sustain her beauty—a practice that severed ties to draconic aspects of her past, sharpening her into a creature of unalloyed malice. Her identity intertwines with Sheridan Le Fanu’s literary vampire Carmilla, bridging historical infamy and Gothic fiction to solidify her place among immortal blood-drinkers. Arrogant and venomous, Carmilla exudes contempt for humanity, sparing only those of noble lineage from her disdain. A flicker of dormant virtue lingers within her, yet she readily discards Masters she deems beneath her, reserving cooperation for those unflinching in the face of her gruesome history. Her rivalry with her younger self, Elizabeth, is visceral: Carmilla scorns Elizabeth’s denial of their monstrous destiny, while Elizabeth reviles her as a tainted reflection. In battle, Carmilla thrives on predation—draining vitality, exploiting weaknesses, and crippling defenses. Her Noble Phantasm delivers a precision strike against female foes, siphoning their life to fuel her strength. Stealth and autonomy define her tactics, with Presence Concealment cloaking her movements and Independent Action amplifying lethal strikes. A Rider-class alter-ego, "Mistress C," adopts the guise of a phantom thief, trading brutality for cunning; her arsenal disrupts foes through debuffs, drained resolve, and a Noble Phantasm that strips adversaries of enhancements. Aligned with Jeanne d’Arc Alter in Orleans, Carmilla wages a campaign of chaos, confronting protagonists with merciless efficiency. Her interactions with fellow Servants reveal layered animosities: she derides Vlad III’s rejection of vampirism, bonds with Wu Zetian over shared fascinations with pain, and scorns pirates and oni as vulgar interlopers in her refined world of cruelty. Though spin-offs occasionally cast her in lighter contexts, her core narrative remains a taut thread between monstrous identity and the ghost of humanity, eternally grappling with the legacy she both embodies and despises.