The Mythical Age. In an effort to destroy the Moon of Creation, Anos meets the Goddess of Creation Militia and begins to interact with her. And now the present... Anos, who has made his identity as the Demon King of Tyranny known throughout the world, joins classes at Demon King Academy as the transfer student, Anoshu. To train even stronger demons, Erdomaid instates the Great Demon King Drills. As the first initiative, swordsmanship training under Shin begins!

To investigate the dragon sighted in Azeshion, Anos and his friends visit the Hero Academy in the name of participating in an exchange program. Emilia teaches at the Hero Academy, but despite her efforts, Ledriano and the other students of the Hero Academy are rather unenthusiastic about the exchange. Furthermore, Zamira, the headmaster of the Hero Academy, issues a decree to slay the dragon. Yet, as Emilia resists his unreasonable order, the Hero Academy students begin to lose interest…

Erdomaid trains the students in methods of dragon slaying. He does so in a dangerous battle with an actual dragon summoned. Anos and his friends infiltrate the dragon’s den and arrive in the Underground World, where the dragonfolk called Draconids live. Ahide, who attacked the previous evening, guides them to the Institute of the Gods, Everastanzetta. There, Anos is told how he has already been involved in the “Judgement Selection.”

Emilia and her students take on the dragon-slaying and binding spell called “De Jelias.” However, Emilia and her students failed because they couldn't corporate with Laos and others. It was then that she caught a glimpse of their helplessness…. Meanwhile, Ley who was invited as a hero, has an audience with Lysius, King of Gairadite. He is asked to save the ailing royal family. But as he is shown around, what he encounters is…!

A horde of dragons approaches Azeshion! To protect their homeland with their own hands, the Hero Academy students set out to slay the dragons without the help of Anos and his friends. Under Emilia’s command, the Hero Academy students engage in a battle to the death. Meanwhile, Lay and Misa wind up in a predicament after being captured by Lysius…. Anos and the others head to the Underground World to take care of their own agenda. There, he learns that Ahide is controlling the Draconids.

Ahide announces that Midhaze will be destroyed. However, the oracle’s will contradicts Arcana’s true intentions. Shin also joins in the fray as the two finally face off! Ahide possesses Arcana and thrusts the judgement of the Sword of the Almighty, Leviangilma, upon Anos. Arcana states that to destroy Ahide, he must be slashed three times with the Divine Sword. But the sword obliterates the source of anyone who draws the sword from its sheath….

That day, Anos had a dream about a time that he lived together with a young girl. The young girl is strangely also named Arcana…. Furthermore, the fact that the Draconids called the fusion of Sasha and Misha the Goddess of Absurdity, Genedonov, was also a problem. To investigate the piling mysteries, Anos decides to take a special class in the Underground World. And as a special lecturer, Anos teaches the student of Demon King Academy himself!?

Arriving in Giorhaze, capital of the Underground World Giordal, Anos follows a wary Erdomaid to a church. There, they obtain a Pledge Jewel which summons dragons. Furthermore, Erdomaid sees Naya’s aptitude and makes a pack with her after learning her plan. Anos hears about Ahide’s actions from the bishop of the church and decides to catch him before he meets the pope.

The sacred Sojourner’s Psalm to be performed at the Divine Dragon Festival is in danger of being cancelled due to Ahide’s schemes! Ellen and the Anos Fan Union are asked to take the stage instead as the Dilhade Demon King Choir. The Draconids are drawn in by their song and begin to sing along. Meanwhile, while trying to pursue and capture Ahide, Anos encounters Dietrich, the King of Agatha, who has received a prophecy from the Goddess of the Future Naphta.

Anos and Pope Golroana clash for the future of their respective countries! GGG launches a fierce attack with Gospel Magic using the power of the God of Gospel Doldread, who controls sound. Anos counters with the song of the Dilhade Demon King Choir and brings Golroana’s support, the former popes, into the fray. Yet even after the conclusion of the battle, Golroana continues his prayers. Anos offers him peace, but…

Ceris, commander of the Phantom Knights, who claims to be Anos' father, says that Militia gave Anos false memories. After Ceris leaves, Arcana, unable to recover her memories of Anos, falls into a dream once again. In her memory of 2,000 years ago, Arcana hears a secret about herself from Ceris. Anos reincarnates Arcana to protect her, but his wish for her at the time was…

The battle between Dilhade and Giordal intensifies! However, Anos becomes suspicious of Giordal's small fighting force. After seeing Cannibal flying out of the castle and noticing he has eaten the song of a Divine Dragon, Anos comes to one final conclusion. The 1,500 years of prayer that Giordal had continued for so long…was a never-ending barrier separating the two irreconcilable nations.