The episode begins with Leo revealing to Selia that he revived her as the Vampire Queen using ancient magic rather than a holy sword. Selia learns that her weakened state is due to a lack of mana and that she must consume Leo's blood to replenish her mana reserves. Selia shares her past, explaining that she and Regina were admitted to the Excalibur Academy after their family was killed in an attack by the Void. She participated in dangerous missions to reawaken her Holy Sword.

At the academy, Leo undergoes a test to determine what kind of Holy Sword he possesses. During the test, he accidentally destroys a series of Void simulators, arousing suspicion. Musel Rhodes, a high-ranking Holy Swordsman, offers to conduct Leo's examination personally. A battle ensues, with Selia standing by Leo's side as his protector. Musel sets a condition: if they lose, Selia must join his squad. During the fight, Selia awakens her Holy Sword and defeats Musel, forcing him to surrender.

Selia and Leo celebrate the awakening of her Holy Sword and his admission into the 18th. Selia decides that Leo should stay in her room since she was the one who found him. Meanwhile, Leo's demonic servants, Blackus and Shary, continue their investigations. Blackus discovers a massive mana crystal that powers the city, while Shary learns that no one remembers the war from a thousand years ago.

The episode ends with a mysterious scene in which a voice whispers, "Le...o...nis."