A flashback from 2,000 years ago depicts a battle between Anos Voldigoad, his right-hand Shin Reglia, the Mother of Spirits Reno, and the god Nosgalia in the spirit forest of Aharthern. After, Anos orders Shin to guard Reno. In the present, Anos and his friends/classmates return to their everyday school lives and receive a new official homeroom teacher, one of the Four Evil Kings called Erdomaid DittiJohn. In reality, Nosgalia has taken over Erdomaid's body. Meanwhile, another conspiracy to kill
Anos and friends battle their separate foes in various different ways, but they do not go down easily. Later, Melhais reports that the humans still hold contempt and fear for Avos Dilhevia despite witnessing what transpired over Azesion and advises Anos announce Avos was a fake at the ceremony to unveil Anos as the true second coming of the Demon King. Anos finally learns who the head of the Unitarians is.
Anos and the team, along with Nosgalia/Erdomaid, make their way to Azesion to open the path to Aharthern to hopefully meet with Shin. In order to get to the forest, Anos makes a deal with an unknown girl, later revealed to be named Lena, to take her with them. After revealing the path, they are guided through the forest by the titi sprites. Upon arriving, they are surprised by the other three of the other Four Evil Kings--Gilysiris Dello, Kyhilam Jiste, and Eges Code--and forced to attend a spir
In order to visit the Spirit King, Anos and his team continue to go through trials provided by the Great Tree Spirit Enyunien. The next trial, “The staircase of Geunier” is a trial where they must choose the 5 correct paths out of the 20 paths before them, which appears to be a game entirely dependent on luck. However, thanks to the advice from Lena, Anos and the team individually made their ways to the top. Lay and Misa arrive to the Spirit King’s castle first, and engage in the final trial!
Misa is revealed to be the true Avos Dilhevia and she is real cocky and annoying, ordering the eradication of all mixed-blood demons. In order to save them all, Anos and company must escape the spirit school. In Dilhade, a purge perpetrated by demon "elites" begins to hunt down all mixed-bloods, and Anos devises a plan to solve the issue.
Anos and the other members of Team Anos appear in the dungeon in his original castle to infiltrate. They run into Revest Aynie and Ms. Meno, revealing more people who still believe in Anos and not the imposter. Anos goes back in time 2,000 years in order to learn what happened with Shin, Reno, and Misa. They learn Lena is the Love Fairy, Fran.
Still in the past, Anos, Shin, Reno, and the others speak to the Great Tree of War before she passes on, and she grants all but Anos a boon. After, they all end up back in the spirit school, and Shin and Reno's relationship grows. Later, the events that transpired between Shin, Reno, Nosgalia, and pre-possession Erdomaid are revealed.
2,000 years ago, a child attempted to see the Demon King but was turned away, as he was already reincarnated. In Aharthern, Anos tries to find a way to destroy Avos without also killing Misa. He also learns about some events that happened in Dilhade after he reincarnated, which leads him to intervene in past events and save Igareth, the child from before and the seventh prince of Azesion. As thanks, Igareth agrees to spread a rumor for Anos to change the future.
Still in the past, Anos and Misha eavesdrop on Erdomaid and his henchman discussing Erdomaid's plan to acquire divine power from Nosgalia. Yet more of the past is revealed in a flashback with Kanon, Shin, and Reno. Shin reminisces on his first meeting with Anos and how it changed his life.
Back in the present, everyone returns, distraught about the past's events but emboldened with new purpose. They begin their invasion to depose Avos. Anos and Lay confront Avos together and Anos's manipulation of the past bears fruit. Shin and Anos finally meet again in the present and have a heart-to-heart.
Lay challenges Avos to liberate Misa whom he loves. However, Heavenly Father God NousGalia aids Avos, and seals Lay’s power of Evansmana. There, Anos and Shin arrive. Shin fights NousGalia once again to avenge his late wife, but he struggles against the enormous power of God. Then, he hears a voice for the first time in two thousand years...
Avos claims the Demon King's sword, Venuzdonoa, and an all-out fight between her and Anos begins. Nosgalia returns when Anos "defeats" Avos, after his apparent defeat earlier, and claims the prophecy of Anos's downfall is nigh. Erdomaid and Anos form a contract. The tragedy of Shin, Reno, and Misa is reconciled and Anos retakes his rightful throne after 2,000 years. However, he realizes part of his memory is missing.
In the past, Anos talked with the Goddess of Creation Militia about how the world functioned on a cycle of mass death and rebirth and that such a system should perish. Over the course of several years, they became friends. In the present, Anos begins attending school as Anosh Poticoal, and Shin becomes a new instructor and proceeds to be an overprotective father. An underground resistance group that opposes Anos's new equality edicts is growing and they have a secret weapon, though Anos does not
Dragon sightings and citizen disappearances are reported in Azesion, which Anos intends to deal with by having joint human/demon training with the help of Emilia. Emilia struggles to adjust to her new teaching position at the Hero Academy. Anos and Team have some lakeside fun. A cardinal named Ahid Alovo Agartz from Jirodal, the Kingdom of the Divine Dragon, makes contact with Anos/Anosh, who was apparently selected as a god's Chosen for the Judgement Selection, unbeknownst to him.
Erdomaid leads the Hero and Demon Academy students through dragon slaying training. Anos/Anosh shows a surprising dominion over dragons and demands they show him their nest in order to gain more information about Jiordal and the Judgement Selection. Once there, he learns more about the Selected 8, those chosen for the opportunity to become a god.
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.
Ahid threatens Dilhade, Anos plans to free the goddess Arcana, and Ahid and Anos duel. After the duel ends, Arcana professes to Anos that she cannot remember who she was before becoming a Selection God but does remember she wanted to be a kind god. Anos gives her the push she needs to move forward. Emilia is made the new headmaster of the Hero Academy.
Arcana dreams of her childhood, seemingly having a young Anos as her older brother, and begins living with him in reality. The gang seeks to understand the nature of Aisha, the name Anos gives Misha and Sasha's combined form, and Arcana's pre-reincarnated state. Additionally, they discuss finding Anos's missing memories. In order to do so, Anos becomes a temporary substitute teacher for their class, and he and Shin show off the depth of their love for each other.
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.
A religious festival held for sojourners to Jiordal is held but is interrupted by Ahid, only to be rescued by the Anos Fan Club. Anos meets with another Selection candidate, Diedrich Kreizen Agatha, king of Agatha, and they team up to meet the pope, Golroana Delo Jiordal. They duel and part with mututal respect. Anos learns what god chose him for the Judgement Selection.
Anos fights Pope Golroana to force him to reveal the location of the God of Vestiges, Liebarschend, in order to discover his and Arcana's lost memories. Anos and Arcana continue their shared dream. The next day, they go after Liebarschend and run into Eges Code and Kyhilam Jiste again. A strange man from the shared dream, Ceris, professes himself to be Ceris Voldigoad, Anos's father from his previous life.
Ceris reveals part of his plan to Anos and the rest, then absconds. Anos and Arcana finish their dream, where it is revealed they are not blood related but still see each other as family. The histories of Arcana, the Goddess of Lies and Betrayal Genedonov, and Jiordal are explained by Ceris, and an attack on the surface world begins.
The battle to defend the surface proceeds, and Cannibal, Naya's dragon summon, allows Anos to learn the underground world is actually inside a divine dragon. Anos, Liebarschend, and Pope Golroana fight. It is discovered Arcana lied about her memories and she is actually the goddess Genedonov, but Anos does not care and still declares her as his little sister. Meanwhile, Anos is still missing his memories.