Battles for ancient kingdoms are nothing compared to the battles of a classroom! Awakening from magical stasis after a thousand years, the Dark Lord Leonis suddenly finds himself in the body of a ten-year-old boy! He quickly meets Riselia, a girl confronting the Voids, creatures that have nearly exterminated humanity. Determined to uncover the mysteries of this strange new era, Leonis enrolls in Excalibur Academy, a school that trains students to fight back against these enigmatic monsters. Could the Voids hold some connection to Leonis's past?

One thousand years ago, Leonis Death Magnus, undead sorcerer and the greatest of the Dark Lords, entered magical stasis during a climactic battle. When he awakens, he finds a beautiful silver-haired young woman named Riselia standing before him. More shockingly, Leonis has been transformed into a ten-year-old boy! Now he’ll have to adapt to this strange era and deal with the twisted monsters called Voids—all while keeping his true powers a secret from his lovely new guardian.

At the evening party aboard the Hyperion, a group of terrorists take the fourth princess of the empire and the entire ship hostage. Time is running out for Leonis and his friends to rescue the princess and prevent everyone on the ship from sinking to their watery graves—and what lurks beneath the surface is far more sinister than a mere rebellion. A dangerous mastermind sits at the center of the plot, and perhaps she holds a clue to the goddess Leonis has been seeking all this time...

After a tough battle, Leonis has managed to protect the Seventh Assault Garden from the attack by the Archsage, Arakael. Soon, he gets wind of the Imperial princess’s visit to Excalibur Academy and attempts to make her acquaintance...but meanwhile, in the shadows, the fearsome scheme of the “demon sword wielders” is beginning to take shape.

AN OLD FRIEND RETURNS With a holiday called the Holy Light Festival fast approaching, the girls of the eighteenth platoon decide to host a haunted café in their dorm. The event is meant to celebrate the arrival of the Sixth Assault Garden, home to Elfiné’s older sister, Clauvia. The mischievous woman is part of a research team that recently made an incredible discovery in the northern tundra—a massive creature sealed in impervious ice. Much to his astonishment, Leonis recognizes the winged beast as an old rival he never managed to beat. When the monster is set loose to wreak havoc, will Leonis manage to take it down in time?

THE GODDESS’S CALL ​A recent rash of incidents has seen Holy Swords spiraling out of control and becoming twisted weapons known as Demon Swords. No one is sure as to the cause, but every Holy Swordsman affected claims to have heard the voice of a goddess, a detail that catches Leonis’s attention. However, there’s no time to investigate, as he and the rest of the eighteenth platoon are sent on a mission with other students to eradicate a Void Hive that crops up in Necrozoa—the site where Riselia found Leonis. So many Voids appearing in such a conspicuous place…could this be connected to the Demon Swords and Leonis’s past?

After the dust settles from the Hyperion incident, Excalibur Academy receives a strange distress signal—one that appears to be from the Third Assault Garden. The problem? The Third Assault Garden should have been destroyed by Voids six years ago! Determined to find out what happened to her birthplace, Riselia leads the eighteenth platoon on a new mission: exploring the abandoned city. But what awaits them may be more than just ghosts from the past...