Y is the daughter of Grace, a famous Rhyhorn racer. Since her childhood, Y has been raised by Grace to follow in her footsteps as a Rhyhorn racer as well. Annoyed at her mother's attempts to decide her future without her consent, Y rebelled and chose to attend Vaniville Town's Sky Trainer academy to learn how to become a Sky Trainer instead. This decision however, spiked many arguments between mother and child. For her skills, she is given the title of "Flyer" (翔ぶ者 Flyer).