|“||Elves and humans... Your dreams and ambitions make such excellent playthings!!||”|
The devil is a tall humanoid with a pair of black, bat-like wings, black horns, clawed hands, and a long, arrow-tipped tail. His pale skin is mostly covered by a black coating and black lines and wrinkles. His teeth are pointed and black, and his irises are red.
Without a body, the devil appears as a dark-colored cloud of gas with eyes and a mouth.
This devil is a wicked and cruel individual. He looked down on both humans and elves, seeing them as his play things and a means to an end. He is shown to be extremely sadistic as he found joy in the despair of others, such as laughing at Patolli's despaired face when the Devil reveals himself as the one who orchestrated the Elves' destruction and has been manipulating Patolli the entire time.
This sadistic side also exposed a great amount of arrogance, such as how he mockingly revealed everything to Patolli and another time when he revealed his plans to the first Magic Emperor. Both cases, he believed they could do nothing to defeat or stop him even if he reveals his intentions and involvement.
The devil's actions came from a deep desire for a body just so he can properly manifest himself and unleash chaos wherever he goes. This displays an extremely selfish side as the devil didn't care what methods he had to use in order to achieve that goal.
All these aspects accumulate to him lacking any morality on how little he thought of his actions toward humans and elves alike,this is further proven true by Yami,who after sensing his Ki can only sense nothing but malicious intent from the devil.
This proved to be his own undoing as he constantly underestimated his opponents which ultimately leads to his demise. In his final moments, the devil expressed shock at the comprehension that he was defeated.
The devil possesses a Clover Kingdom minister and orchestrates the royals' plot to steal the Elf Tribe's magic. He sets up a trap to keep Lemiel Silvamillion Clover from attending the wedding. After the massacre, Licht's despair turns his grimoire into a five-leaf clover. The devil attempts to take over Licht's body, but Lemiel's arrival rouses Licht, who then uses the magic stones to transform into a giant demon, refusing to surrender his body to the devil. The devil watches with amusement as Lemiel fights and kills Licht.
Afterward, the devil tries to steal Licht's grimoire, but Secre Swallowtail uses the magic stones to seal him within an Eternal Prison. Before the seal finishes, the devil summons the magic stones to himself and uses them to suspend the elves' souls and to set them and himself to reincarnate in the future.
Five centuries later, Patolli uses the magic stones and the tree of life monument to reincarnate the elves and, unknowingly, the devil. The devil possesses Baval and enters the Shadow Palace once it is opened. He then switches to Ronne's body and joins Patolli and Rhya in waiting for the arrival of Yuno and the eleventh magic stone. The devil manages to steal the stone from Yuno, and when Rhya grows suspicious of Ronne, the devil blasts a hole in Rhya's abdomen.
While Patolli is preoccupied with healing Rhya, the devil places the stone in the pedestal and summons his original body from the underworld. He then reveals the truth about the massacre and the elves' reincarnation, but Patolli refuses to believe it and lashes out with swords of light. The devil sends the attack back, and Yuno pulls Patolli and Rhya out of harm's way. Yuno tries attacking the devil himself, but the devil effortlessly blocks the attack and boasts about his Kotodama Magic.
The devil chooses to ignore Asta and Mimosa Vermillion when they drop into the chamber. Instead, he summons Patolli to him and begins torturing the elf. Yuno and Asta try to interfere, but the devil summons a storm of swords to distract the pair and then calls down a wall to smash them into the floor. The devil returns his attention to Patolli and forces the elf to face the truth that Patolli was following the devil's plan, not Licht's. The devil laughs at Patolli's anguish. Refusing to give up, Yuno and Asta stand back up and attack the devil together, cracking the devil's arm. The devil heals his arm and compliments the boys' for injuring him. The devil does not recognize Asta's devil but offers to let it keep Asta's grimoire.
While he waits for Patolli's grimoire to be corrupted into a five-leaf clover, the devil reveals his plan to take the grimoire to the living world and unleash his true power and form. The devil grabs the grimoire, and when Asta and Yuno try to stop him, he releases Patolli who has become a dark elf. The devil flies away toward the palace's exit while the boys are busy fighting Patolli.
The devil reaches the topmost chamber and is confronted by Licht. The two exchange spells until the devil creates bindings that restrain Licht and his sword. The devil throws a large spear at the bound elf, but Charla manages to redirect the spear to miss and Yami Sukehiro cuts the bindings. The devil renews his attacks and, after Yami cuts off the devil's arm and wing, compliments Yami and Charla's coordination. They continue fighting, and when the devil dodges one of Yami's attacks, Licht absorbs and releases the attack and manages to sever the devil's tail. The devil then uses the grimoire to summon a flood of magic from the underworld. The magic eats other magic and lifeforce, and the devil directs it to flood down and swallow everyone in the Shadow Palace.
Asta, Yuno, and Patolli reach the chamber, and the devil is impressed that they reversed the dark elf transformation. Suddenly Lemiel and Secre crash into the chamber and confront the devil. The devil mocks Lemiel and Licht's reunion and attacks them, but the pair are able destroy the devil's magic due to them being tainted by magic from the underworld. They attack him directly and he is almost overwhelmed by their quick teamwork. The devil creates a trident that shatters Lemiel's light sword and severs the prince's left arm. Before the devil can kill Lemiel, Asta is thrown and blocks the trident with Anti Magic. The devil forces Asta back and summons a storm of swords to distract the boy.
The devil taunts the others for their weak magic, so Licht draws on the power of the other elves and hits the devil with the collected power. The devil's body disintegrates and his portal to underworld is also destroyed. His heart, however, survives and regenerates his body. When Asta draws on more Anti Magic and is pulled toward the devil, the devil tries to block the attack with his trident, but the Demon-Slayer Sword cuts through it. The devil decides to show off his superiority to Asta's devil and summons more underworld monsters, which draw Asta away from the devil. The devil mocks Patolli when the elf manages to use Demon Light Magic against the monsters, but is left speechless when Yuno cuts huge swaths with Spirit of Zephyr.
Asta and Yuno charge toward the devil, and Yuno uses his new sword to propel Asta forward, catching the devil off guard. Asta's Black Divider pierces the devil's chest but misses his heart because the devil moved it to the other side. Furious, the devil opens more mouths on his body to summon multiple portals with various monsters pouring out in an attempt to destroy the entire Shadow Palace. While Asta and Yuno are occupied cutting down those, the devil summons more powerful giant monsters.
The devil watches as Yuno flies toward him and cuts apart the monsters, but he loses sight of Asta who hides in the shadows of the monster pieces and attacks from behind the devil. The boys land a pincer hit on the devil but fail to kill him as Asta's black form fails. The devil then grabs hold of both of them and prepares to kill them. Suddenly, Yami's Dark Cloaked Dimension Slash: Equinox bisects the devil. His mouths begin vomiting as he tries to use his magic. The devil manages to create some iron spears, but Yuno destroys them, giving Secre time to heal Asta. With a giant Black Divider, Asta cleaves the devil's torso and destroys the heart.
- Kotodama Magic: The devil uses this magic attribute to alter his surroundings through speech and to manifest physical and magical objects. While using Patolli's grimoire, the devil is able to summon various monsters from the underworld that absorb normal magic and lifeforce.
- Reincarnation Magic: The devil uses this form of magic to revive souls of the dead in bodies of the living.
- Immense Magic Power: The devil possesses an immense amount of mana, more than even the most powerful elves.
- Possession: The devil is capable of possessing the bodies of others, including elves and humans.
- Grimoire: The devil possesses a five-leaf clover grimoire that augments his Kotodama Magic. It used to be a four-leaf clover grimoire that belonged to Patolli, before being corrupted by the devil.
- "Elves and humans... Your dreams and ambitions make such excellent playthings!!" 「エルフも... 人間も... アナタ達の夢や欲望はサイコォォォの玩具 (オモチャ) ですよ...!! "Erufu mo... Ningen mo... Anata-tachi no yume ya yokubō wa saiko~o~o~o no omochadesu yo...!!"」