Utahime: The Songstress 

It was once a land in which the peace was protected by a king who ruled from the center of the empire. The singers who lived in the villages of the land supported the king with their song. However, they lived as if in captivity and her destiny was to sing constantly. The strength of the singers has been transmitted only from mother to daughter. The singers were closed by order of the king in towers and should always sing lullabies. If a village lost his song, it was faced with ruin. The siblings Kain and Maria have a singer as mother. When Kain finds out that the village uses the singers, he protects his sister Maria to preserve her from such a destiny... Note: Includes the one shot Darika (ダリカ).