In a "caste (class) society," a person's value is determined by their skill rank. Osamu, a high school student with no special abilities, is scorned as "incompetent" and subjected to brutal bullying by his family and classmates. But one day, driven to the brink of death, he awakens to the power of "Learning," which allows him to steal the skills that have tormented him. Now, all of the oppression he endured every day will be transformed into the power of revenge! Standing in his way is an S-class party known as the nation's heroes. The curtain rises on an unrivaled drama of "skill revenge" that will overturn a society that mocks the weak!