After a devastating war, the world teems with superpowered individuals and fearsome monsters. As the myth of the ancient weapon, "Armor End", resurfaces, young Kiro yearns to join the legendary royal guards to receive "Gratia", a wish-granting blessing from the king, to cure his cursed mother. As he meets up with Jinn, an ex-soldier seeking to unravel the truth behind a nightmarish failed mission. Can Kiro rise above the darkness ?! And save his mother without losing himself in the process ?!