Dungeon Builder: The Demon King's Labyrinth is a Modern City! (Manga) Vol. 1

WE BUILT THIS CITY ON ROCKS AND HOLES Procel, newly minted Demon Lord of Creation, faces off against an emerald dragon summoned by Stolas, the Demon Lord of Wind. Berserk with rage, Stolas will stop at nothing to defeat Procel. But even if he survives the battle, does Procel have what it takes to fulfill his vision of building a city-size dungeon in the forbidding landscape of this strange new world?