In the heart of a desolate war, a girl named Korou seeks death. Joining a top-tier unit commanded by Kano, renowned as 'the immortal,' she embraces peril as a fighter pilot. Despite her death wish, her squadmates safeguard her, nurturing her growth amidst relentless enemy assaults. Evolving into a skilled aviator, Korou earns the title 'Sky Sovereign' for her fearless exploits in the skies.