It is set between two worlds, the real world in which we live and another world where dragons live. Nagi is a fantasy-loving high-school girl who lives in the real world. She has a special ability that allows her to visualize colors whenever she hears sounds and doesn't feel she fits in with her surroundings. From some point, she starts to be troubled by repeated daydreams of flying in the sky. Meanwhile, Tyme lives in the alternate world of Upananta, where a strange phenomenon occurs in which many flying islands fall from the sky. Akuta Sky Group, led by the hero Akuta, have been trying to save people from the dangers of the world collapsing. Tyme admires Akuta and decides to join his group as a dragon rider, but he isn't happy as he isn't able to hear the voices of the dragons and ends up being considered a "dropout". One day, the two worlds intersect, and Nagi meets Time from Upananta. Though they both come from different worlds, they find similarities in the fact they are different from those around them.