In a world, different from ours, years ago an extraordinary hero arrived to the kingdom of Distinia, and gave himself completely to achieve peace among all races.
But on the day of the final battle, at the climax of the encounter with the demon king Toma, the hero disappeared without a trace.
Years later, in our world, we find Setsu, who has reincarnated keeping his old powers, starting his day in high school. And Setsu’s childhood friend Yuhi tells him that he should cut his hair.
Yuhi offers to cut it, like she used to when they were kids, and Setsu tells her that would be a good idea.
Suddenly, a strange energy surrounds the classroom, and without noticing, all the students appear in the middle of a battlefield, surrounded by ogres and knights.
While everyone looks scared, for some reason, Setsu seems to understand he has returned to the world he saved before, and immediately orders everyone to get away from the place.
The troops of the kingdom appear, and in front of them is Elka, who leads them to a safe place.
Later, the students appear in front of the King of Distinia, informing them that they have been summoned from another world to become heroes.
They claim that the peace achieved by the legendary hero is in danger, and that the demons are about to attack the kingdom again. With no choice but to fight, the students begin to prepare.
But for Setsu, there’s no need, and as soon as Elka sees that he’s slacking off, she discovers that he’s the legendary hero everyone looks up to.
Setsu tells her what happened after his last battle and how he reappeared in his world, only to be summoned again.
After being reunited with his old battle companions, Setsu realizes that Toma, the demon he fought, has also regained his powers and is apparently moving his troops.
Setsu decides to leave the kingdom and seek answers to his doubts, but before doing so, he says goodbye to Yuhi, who seems to have a high affinity with the use of magic in this world.