Lilith, codenamed Black Lilith, stands as the enigmatic founder and supreme leader of the Kisaragi Corporation, doubling as its chief scientist. Her sleek black bob cut and ever-present white lab coat underscore a persona blending theatrical flair and scientific ambition. Prone to chuunibyo theatrics, she delivers flamboyant monologues and cackles with melodramatic menace, her genius overshadowed by reckless overconfidence. Rarely testing prototypes, her unchecked innovations—like a desert-terraforming soybean project or a contentious monopoly claim on the color black—often backfire, cementing her status as Kisaragi’s least revered leader.

Orphaned by civil war and raised in a Kisaragi facility, her tragic origins inspired ally Astaroth’s quest for world domination. Her inventions, from interdimensional teleporters to the disdainful combat android Alice, showcase brilliance marred by impulsivity. Cybernetic upgrades grant her eight laser-firing tentacles, neural-linked weapon control, and an energy chip tapping Kisaragi’s grid for infinite ammunition—though alternate realms force her to harvest "Evil Points" for power.

Her relationships teeter between camaraderie and rivalry. She treats Combat Agent Six like a mischievous younger brother, bonding over games while enduring his jabs, but clashes with Astaroth and Belial over their elegance and her own chaotic antics. Brief alliances crumble under her betrayals, fueled by envy and a hunger for personal glory.

Notable exploits include accidentally toppling a Demon Lord during a botched rescue of Six, a fleeting custody stint, and a doomed rebellion. Her legacy persists through Kisaragi’s Evil Point system, her voice echoing across updates, and the organization’s shift to black uniforms following her chromatic crusade. Outside scheming, she obsesses over puzzle games and "Magical Girl Puikyua," topping internal polls for "Most Antisocial" and "Most Scheming." The revelation of her surname, Yasuda—leaked by Six—offers a rare glimpse beneath her crafted enigma.