Simoun

In the world of Daikuuriku, where individuals are born female, the process of sex selection occurs at age 17. The theocratic nation of Simulacrum, a bastion of peace, is safeguarded by magical flying machines known as "Simoun." These aerial vessels can only be piloted by young girls who have yet to select a sex, and they possess the extraordinary ability to activate the "Ri Maajon" power, which enables them to destroy a large number of enemies simultaneously. As the industrialized nation of Argentum seeks to invade Simulacrum to acquire the secret of the Simoun, war erupts, drawing the Simoun pilots, known as "Sibyllae," into a one-sided battle. The Sibyllae are granted an exemption from choosing a permanent sex as long as they continue to fly the Simoun. Aaeru, a determined young Sibylla with a mysterious past, and Neviril, the leader of Chor Tempest, Simulacrum's elite Simoun squadron, must navigate the conflict within their ranks and in the skies as they lead their fellow Sibyllae through the turmoil.