Ai Enma, the Hell Girl, emerged in 17th-century Mutsumi Village, her childhood marked by ostracization over whispered rumors of uncanny powers. At seven, villagers chose her as a sacrifice to pacify a mountain god. Her parents defied the ritual, prompting a violent confrontation that ended with the family buried alive in their hiding place—a betrayal sealed by her cousin Sentarou Shibata, once her protector. Escaping the grave, Ai ignited the village in flames, sparing only Sentarou, who fled with manic laughter. This act summoned the Master of Hell, who forged a pact: her parents’ souls would evade eternal suffering if she became Hell Girl, an emotionless ferrywoman guiding vengeful souls to damnation. For over four centuries, Ai delivered straw dolls tied with crimson strings to those consumed by hatred. Clients who pulled the strings consigned their foes—and themselves—to Hell. Her tools evolved from ema tablets to a shadowy midnight website, accessible only to the deeply aggrieved. Bound by neutrality, she occasionally faltered, torching Sentarou’s temple or hesitating to doom innocents—fleeting cracks in her stoic veneer. Trapped in the body of a thirteen-year-old, Ai bears pale skin, ink-black hair, and piercing scarlet eyes, her kimono shifting with the seasons: sakura blooms, undulating patterns, floral motifs. She dwells in the Realm of Eternal Twilight, flanked by three yōkai aides—Wanyuudou, a sentient carriage wheel; Ichimokuren, a katana spirit; and Hone Onna, a skeletal enchantress—all united by disdain for mortal frailty. In *Two Mirrors*, her detachment wavers. Her aides investigate grievances to ease her burden, while the enigmatic Kikuri sows chaos, testing Ai’s authority. A town’s corruption of Hell Correspondence mirrors her trauma, stirring buried anguish. Later seasons deepen her duality: *Three Vessels* sees her possessing schoolgirl Yuzuki Mikage, intertwining their fates with themes of inherited sin. *The Fourth Twilight* introduces Michiru, a protégé reflecting vengeance’s cyclical grip. Though bound by duty, Ai’s silent torment over condemning the guiltless and fleeting emotional flickers hint at lingering humanity. Her existence balances icy obligation against latent empathy, framed by eons of observing humanity’s cruelty and fragility—a paradox etched in every whispered curse she enables.