Imouto ga Onna Kishi Gakuen ni Nyuugaku Shitara Nazeka Kyuukoku no Eiyuu ni Narimashita. Boku ga.

My sister enrolled in an all-girls knight training academy. Even at the kingdom's most prestigious academy, my little sister, a brilliant girl, excels in every subject... "I'm telling you that my brother is so much stronger than me!" No, I'm just an ordinary guy.......? (*That's not true. He just do