My Hero Academia: The Return of Hero Killer Stain, Explained

Chizome Akaguro, popularly known by his title Hero Killer, Stain, is a villain and ex-vigilante who dislikes the corrupted hero society and the fake heroes in it. Looking up to All Might as the only true hero, Stain decided to rid the world of fake heroes by killing them. Chizome, like many other people, began his life as a child who feared and respected All Might. He enrolled in a private hero school in an attempt to emulate its graduates, only to discover the institution was rife with evil and corruption. Chizome dropped out of school to pursue a career as the vigilante Stendhal. After some time had passed, he embraced the moniker of Hero Killer and vowed to rid the world of all false heroes.