Dabi, born Toya Todoroki, is the firstborn of Pro Hero Endeavor (Enji Todoroki) and Rei Himura, conceived through a Quirk marriage designed to produce an heir surpassing All Might. Inheriting his father’s Blueflame Quirk—a fire ability surpassing Endeavor’s Hellflame in heat—Toya paradoxically possessed his mother’s cold-resistant physiology, rendering his body vulnerable to self-inflicted burns. Ignoring parental and medical warnings, he relentlessly trained to meet Endeavor’s expectations, sustaining irreversible damage that prompted his father to abandon him in favor of grooming his younger brother, Shoto. Crushed by years of neglect, Toya’s resolve fractured at age 13 during a solitary training session on Sekoto Peak. Overwhelmed by rage, his Quirk spiraled into an inferno that ravaged the mountainside. Presumed dead after plunging into a lake to survive, Toya was recovered by All For One, who subjected him to a three-year coma. He awoke with a corpse-like body rebuilt from regenerative tissue, stripped of pain perception but marred by disfigurement. Returning home, he witnessed Endeavor’s relentless abuse of Shoto, extinguishing any hope of familial redemption. Discarding his birth name, he embraced the identity of Dabi, vowing to dismantle Endeavor’s legacy. Operating within the League of Villains and Paranormal Liberation Front, Dabi ascended as a lieutenant, cloaking his vendetta in Stain’s rhetoric to destabilize hero society. His Blueflame Quirk unleashed searing blue fire exceeding 2,000°C, enabling devastating techniques like Flashfire Fist and Hell Spider—mimics of Endeavor’s signature moves pushed to self-immolating extremes. Though his reconstructed body endured prolonged combat, it steadily deteriorated, fracturing under the strain of his power. The Final War arc ignited Dabi’s ultimate gambit: publicly unmasking himself as Toya Todoroki to expose Endeavor’s crimes. In a bid to annihilate his family and hero society, he triggered a cataclysmic explosion, clashing with Shoto and Endeavor until their combined ice Quirks froze his flames mid-combustion, leaving him a skeletal figure encased in ice. Confined to life-support post-war, his charred frame clung to existence. He rejected reconciliation until a final exchange with Shoto unearthed buried remorse, particularly for weaponizing their brotherhood. Years later, Dabi succumbed to his injuries, his grave later visited by Shoto. Dabi’s visage bore jagged purple scars sutured by surgical staples, remnants of Quirk overuse. His once-black hair reverted to its natural white after his identity revelation. His demeanor blended icy detachment with calculated malice, manipulating allies like Hawks and Twice while mocking adversaries. Though he invoked Stain’s philosophy, his crusade centered on personal vengeance, targeting heroes and civilians alike. Fleeting introspection surfaced—regret over Shoto’s suffering—yet his existence remained tethered to erasing Endeavor’s legacy, a pursuit that consumed him utterly.