January 13th, 100 AS, all first-year students of Metropolis High School eagerly awaited the Coming-of-Age Ceremony. On this predetermined day, every 16-year-old would have their moral role decided—whether they would become a Hero or a Villain.
Those deemed Heroes would live dignified lives, guaranteed a promising future, and gain the right to serve as civil officers entrusted with the safety of the people. Meanwhile, those condemned as Villains would receive immense destructive power in exchange for losing their citizenship and being cursed to serve Abomination for eternity.
Mike Barton was just an ordinary student dreaming of a peaceful and successful adult life. However, at the Coming-of-Age Ceremony, he was unexpectedly granted a strange ability called the Extra System.
[You will no longer be bound by the conventional moral compass of the Monument of Truth.]
[You now have the freedom to switch between Hero and Villain sides.]
[The Extra System can exponentially and infinitely increase your power.]
[The Extra System grants you dual Soul Powers from both alignments.]
With this system, Mike could play both roles simultaneously and view the world from different perspectives. He also gradually uncovered the truth behind the Monument of Truth, Abomination, and its connection to the catastrophic events that reshaped the world into what it is today.