Set in the future on a land that, after being marred by long-lasting wars, has settled into a quiet cycle of decline. Sorami Kanata is a 15-year-old girl who fulfills her dream of enlisting in the army and joins a unit of five girls who protect a fortress that looms over a little village. The girls also play music that reverberates across the skies over towns without people and seas without fish.

[Source: AniDB]