魔法が使えないモブキャラに転生したけど、俺だけ使える【最強剣技】で成り上がる～推しの悪役令嬢の兄となった男は破滅フラグを叩き斬り、ゲーム世界で無双する～

あらすじ

Sord, a boy reborn as a rural noble in a world based on a magic RPG, is eager to explore the game he played countless times in his past life. However, he soon faces a shocking truth—he has no talent for magic! Deemed a worthless background character with no impact on the story, Sord resigns himself to a mundane existence… until he stumbles upon a hidden book detailing a long-lost secret sword technique! With this ultimate blade art in hand, he prepares to cut down every disaster flag that threatens his future. No magic? No problem! The strongest swordsman’s legend begins now!