To Marry the Saint, I Must Defeat the Demon King

Leo, the heir of an ancient swordsmanship school, descends from his seclusion to save his declining dojo. Disguising himself as a commoner, he enrolls in a renowned aristocratic academy known across the continent. Intending to stay low-key, he unexpectedly encounters his destined partner. In his quest to marry her, Leo finds himself compelled to defeat the Demon King and save the world. ~This is a slow-paced story where the protagonists, initially indifferent to each other, gradually develop deep feelings as the plot unfolds.