Chizome Akaguro, also known as Hero Killer: Stain, is a notorious villain and former vigilante who gained infamy for killing numerous Pro Heroes. As the main antagonist in the Vs. Hero Killer Arc, Stain's menacing appearance features a distinct hunch, a face devoid of a nose that he removed himself, and a lengthy tongue. Clad in a dark combat suit with metal armor, he brandishes an array of weapons, including a worn katana, daggers, throwing knives, and spiked boots. Known for his blood-red scarf and mask, specifically. His cruel and unforgiving nature stems from a conviction to cleanse society of false heroes, sparing only those he deemed worthy. Despite his extremist views, Stain demonstrates genuine ideals about heroism, aiding heroes against formidable threats. Stain's unparalleled combat abilities, marked by immense speed, strength, and stamina, allows him to defeat numerous Pro Heroes. His Quirk, Bloodcurdle, enables him to paralyze foes upon tasting their blood, showcasing his tactical intellect in battle. Despite his villainous reputation, Stain's complex character reflects a self-righteousness driven by a unique sense of justice and a desire for a genuine hero to prevail.