聖戦記エルナサーガ

In a world torn by war, the kingdom of Ansaz is led by the invincible Prince Sharlvy, whose relentless march threatens the land of Arsatual. At the heart of this conflict is Princess Erna, a young noble who, unlike everyone else in this magic-filled world, possesses no magical abilities. Yet, her unique lack of power may hold the key to wielding the legendary Holy Sword, a weapon said to shape the fate of nations. As Erna and her allies navigate treacherous battles, shifting alliances, and the weight of destiny, they uncover the deeper truths of their world and the bonds that define them. (Unreviewed summary by Grok 2)