Canaan no Shiro: Boukoku no Oujo to Sekai no Hihou, Sore wo Meguru Saikyou Touzoku-dan to Haken Kokka no Daikatsugeki

The story is set in a world where the Aizen Empire has conquered a world previously filled with magic and sword with the might of their guns and artillery. The story follows a group of three thieves rebelling against this established order who accidentally kidnap the princess of a fallen kingdom.