Hunted by the Demon Lord, William and his wife urge their son Arion to flee, revealing the boy is the final 'vessel of anti-magic' needed to destroy the world. Cornered, the parents sacrifice their lives to cast the Twelve Final Seals, binding the Demon Lord but also sealing Arion's magic. A decade later, a now-powerless Arion is scorned and dismissed as 'dead weight' by Headmaster White and the Radiant Academy, which only summons him to fill a seat at a royal gala. As he feels the Demon Lord stirring and the seals weakening, Arion vows to prove the legacy of his family's bloodline to all who have wronged him.