Kai Chisaki, alias Overhaul, is a man in his twenties with short, disheveled brown hair and eyes often rimmed with fatigue. He dons a green overcoat lined with a fur-trimmed collar, rarely seen without his disposable medical gloves and an eerie orange plague doctor mask curving sharply like a raven’s beak. His Quirk, Overhaul, grants him dominion over matter itself: a touch lets him dismantle and reconstruct objects or living tissue at the molecular level. This power fuels both precision healing and grotesque transformations, even fusing his body with others to pilfer their Quirks—a duality of creation and ruin. Raised in an orphanage under Dr. Kyudai Garaki’s watch, Chisaki endured clandestine experiments that warped his psyche. After adoption by the Shie Hassaikai yakuza boss, he usurped leadership, steering the syndicate to reclaim its fading empire through Quirk-destroying bullets. These projectiles, forged from the blood of Eri—the former boss’s captive granddaughter—ignite wars against heroes and underworld rivals alike. A relentless mysophobia drives Chisaki to shun filth with obsessive precision, his mask shielding him from invisible threats. He views Quirks as a societal plague, dubbing their cultural glorification "Hero Syndrome." His obsessive crusade seeks to purge society of Quirks entirely, restoring an era untouched by such power—a mission dictating every cold calculation and alliance. His schemes culminate in violent confrontations with heroes like Mirio Togata and Izuku Midoriya. Though his machinations shape the course of chaos, ambition proves his undoing: his empire crumbles, leaving him shackled in a prison cell, his dream of a Quirkless world unfulfilled.