Bullied, Leo is reborn on his Ability Awakening day. He binds to a System, growing stronger by absorbing negative emotions. Disguised as a weak F-Rank, he uses the System to stage a comeback, defeating bullies, foiling plots, and killing assassins, rejecting Black Obsidian. When a villain plots to devour all Abilities in The Academy, Leo absorbs emotional power of the masses. He counterattacks to defeat the foe and protect his teachers and students, forging a legend.