My Childhood Friend, Whom I Promised to Marry in the Future, Came Back as a Swordsman

Shourai Kekkon shiyou ne, to Yakusoku shita Osananajimi ga Kensei ni Natte Kaettekita: Dorei Datta Shounen wa Kakusei shi Saikyou e Itaru

将来結婚しようね、と約束した幼馴染が剣聖になって帰ってきた～奴隷だった少年は覚醒し最強へ至る～