In the Kingdom of Windbloom, Arika Yumemiya enrolls at Garderobe Academy to become an Otome—a virgin girl capable of wielding a HiME (Highly-advanced Materializing Equipment) that grants destructive powers. Arika also hopes to locate her mother, who was a Meister Otome, the highest rank of Otome serving as the personal bodyguard and super weapon for the specific nation to which they are assigned. During her time at the academy, Arika befriends Nina Wáng, a distinguished Otome student, and Mashiro Blan de Windbloom, the kingdom's current princess. With their support, Arika quickly adapts to the academy's atmosphere, spending her days diligently training, managing social dynamics, and honing her abilities as an Otome. However, Arika soon discovers that the path to becoming an Otome is riddled with dangers and questionable political maneuvers. Confronted with numerous personal dilemmas, Arika must make significant sacrifices if she is to truly achieve her objectives.