The story revolves around Nishimiya Shoko, a grade school student who has impaired hearing. She transfers into a new school, where she is bullied by her classmates, especially Ishida Shouya. It gets to the point where she transfers to another school and as a result, Shouya is ostracized and bullied himself, with no friends to speak to and no plans for the future. Years later, he sets himself on a path to redemption.
In the land of Iolph, all the people stop aging in their mid-teens and can live for hundreds of years. One resident, Maquia, feels lonely despite the peaceful and idyllic land she lives in. But one day, the Mesarte army invades Iolph, seeking the peoples' blood for their immortality. Maquia manages to escape the destruction and chaos of war, but with no home or people, she becomes a wanderer in a dark forest. She comes across Erial, an infant mortal boy who has lost his parents, and becomes his guardian. The story follows the relationship that evolves between the two as Erial grows up while Maquia does not.