歴代最年少の騎士であり、伝説の《剣聖》の生まれ変わりのアルタ。次期国王候補である《剣聖姫》の少女イリスの護衛として学園に派遣されるが、「私と本気で戦ってください」護衛するはずのイリスから突然戦いを挑まれてしまい――!? Alta is the youngest knight in history and the reincarnation of the legendary “Sword Saint”. He is dispatched to the school to protect Iris, the “Sword Saint Princess” who is the next king’s candidate, but “Please fight with me seriously”, but Iris, who is supposed to be his escort, suddenly challenges him to a fight…!