Rakudai Kishi no Cavalry

The \"school sword action\" story revolves around Magic Knights, modern magic-users who fight with weapons converted from their souls. Ikki Kurogane goes to a school for these Magic Knights, but he is the \"Failed Knight\" or \"Worst One\" who is failing because he has no magical skills. However, one day, he is challenged to a duel by Stella, a foreign princess and the \"Number One\" student. In this duel, \"the loser must be obedient for life.\"