The Melody of Oblivion

The Melody of Oblivion takes place in a world where humans and monsters coexist, with monsters holding power over the globe since a devastating war in the 20th century. Bokka, a boy intrigued by history, seeks answers about the Meros Warriors who fought against demons. He meets Kurofune, learns about the Meros and their I-bar machines, and discovers he can hear the Melody of Oblivion, a phantom girl hidden away. Bokka's newfound ability allows him to join Kurofune in battles against demons, ultimately aiming to free a world that has lost its beautiful melody, Boukyaku no Senritsu.