The Great Demon Lord's City Development ~The Ideal City Built with Magic, Science, and Monsters

Instead of building a dungeon to feed on the despair of humans, the eccentric Procell used his [Creation] powers to build a city where humans and monsters could live and laugh together. Before long, he became one of the three strongest Demon Lords. However, through a series of events, a jealous fellow Demon Lord sent Procell away to an unknown land. And so, in order to return to the city he built as well as to his beloved monsters, Procell and the [Infinitely Evolving Slime] he came with began to move. However, unbeknownst to him, this new land, the new companions he would meet, and the city and monsters he was separated from…