魂を魔剣に変える能力者≪魔導騎士≫を育成する破軍学園。≪魔導騎士≫となるべく学園に通う少年・黒鉄一輝は、しかし魔法の才能がなく≪落第騎士≫と呼ばれていた。そんな中、最強と名高い美少女騎士・ステラとの出会いが、一輝の「最弱」な学園生活を一変させる！　最底辺から騎士の頂点を目指す、学園ソードアクション開幕!!

There are some humans capable of using magical power to manifest their souls as weapons and control forces beyond normal comprehension. These people are known as Blazers, and those who are recognized as such can undergo training at academies to become Mage-Knights. Ikki Kurogane is an aspiring Mage-Knight, despite being considered the worst student at Hagun Academy as an F-ranked Blazer—the lowest rank possible.

One morning, he accidentally stumbles upon Stella Vermillion, a visiting princess and A-ranked Blazer who has just enrolled at Hagun, in a state of undress. As a result, she challenges him to a duel where the loser will be the winner’s slave. It seems like a surefire win for Stella, but could there be more to Ikki than meets the eye?