Cian is a young man who was born into a family of wealthy aristocrats, so you would expect his life to be nothing but smooth sailing... But during his coming-of-age ceremony, in which one is gifted with magical power, the only thing is receives is a seemingly worthless "cup" that does nothing but have water pour out of it. Because of this, Cian is branded a useless dunce and is exiled to live in the desert of a remote region and serve as a nominal feudal lord!

Despite having hit rock-bottom, Cian doesn't get discouraged and instead aims to revive the barren region. Using the water poured from his "cup", he restores the dried-up oasis and starts to bring smiles back to the faces of the area's residents. That's when his "cup" reawakens is revealed to be the Holy Grail...?! So making full use of his "cup", Cian challenges himself by making regional specialties to sell, raises magical plants, and creates a city just the way he wants!