In this region, there are creatures called "Uma" (Dragon Horses).

Lucie, a girl born in the countryside, lost her parents—both Uma riders—due to a certain incident. The only thing left to her was her own Uma.

To make a living, Lucie decides to become a Uma rider herself. However, the reality she faces in the city is that taxis are everywhere, making Uma obsolete relics of the past.

To make matters worse, Lucie’s Uma refuses to listen to her at all!

This is the story of Lucie and her large, mysterious companion, the Uma, as they struggle and grow together in her journey to become a Uma rider. A heartfelt fantasy about a girl who carries people, goods—and even love.