Ultimate Antihero

Homura Kamishiro, the strongest mage in the world, saved it from the demon king Typhon 5 years ago. Since then, he's known as The Traitor and Fiend Summoner, who sold his soul to inhumane beings. What will happen when he joins New Tokyo Magic Academy's 101st Training Platoon and what mysterious promise he made back in time about its cute leader in cowgirl clothes, Hoshikawa?