Kuusen Madoushi Kouhosei no Kyoukan

Driven from their lands by giant insect-like monsters, humans built cities in the air. To eradicate the threat, mages were sent into battle. Among them was Kanata Age, formerly a valiant warrior known as "Master Black Swordsman," now regarded as the traitor of his special unit. One day, he is sent as an instructor to Team E601. Composed of three strange girls, Misora Whitale, Lecty Eisenach, and Rico Flamel, this team suffers no less than six defeats…