From Old Country Bumpkin to Master Swordsman: My Hotshot Disciples Are All Grown Up Now, and They Won't Leave Me Alone Volume 2 oleh Shigeru Sagazaki

Self-proclaimed “old country bumpkin” Beryl Gardinant has finally settled into his new role as a special instructor for the Liberion Order. After breaking his sword in the fight against Zeno Grable, he seeks out a new blade and stumbles upon yet another of his former students—a skilled blacksmith named Baldur, who promises to forge a custom sword using the monster’s remains. Just one problem: this leaves Beryl without a weapon at his side. One night when Beryl is walking home alone, a young thief takes advantage of his unarmed state and launches a truly unexpected attack—fire magic! And when Beryl consults the commander of the magic corps about this wizard thief, he becomes embroiled in a plot of national proportions. Can Beryl help this young criminal turn their life around? And will any of his pupils finally realize that their “master” is nothing but a normal old man?!