The Misfit of Demon King Academy, Vol. 5 (novel)

With the second coming of the Demon King of Tyranny, Dilhade is finally at peace, but sightings of dragons, which were thought to be extinct, have been reported all over Azesion. When the Demon King Academy and Hero Academy team up to deal with the creatures, they discover an unknown world beneath the ground. Meanwhile, a mysterious man with a god by his side appears before Anos. The man, a draconid, tells him of the Selection, a trial in which eight gods summon representatives to fight each other and the victor becomes a proxy of the gods, and of how Anos has been chosen as one of the representatives. Anos pursues the man to the underground world—the divine capital, Gaelahesta—where he takes down his new “rival” and befriends the familiar yet not-so-familiar god…