Banner of the Stars II

Due to a lack of ambassadors for the recently-conquered worlds the rapidly advancing fleet of the Bebaus brothers leave behind, Lafiel is appointed Territorial Ambassador of the planet Lobnas II. Upon arriving to the planet Jinto and Lafiel discover that the planet was used by the United Mankind as a prison planet and now has a million prisoners on the only inhabited island. The prisoners are parted in three blocks. (myanimelist.net)