The Black Bulls get a sudden visit from Mereleona and she drags them to the strong magic region of the Yultim Volcano. There, the Crimson Lion Kings, as well as their captain, Fuegoleon, and his younger brother Leopold, were waiting for them. Asta and Noelle remember the hot springs they had visited on their previous trip there. Finding new resolve, Magna, Luck, Charmy, Gordon, and Nero all decide to train in the fiery underground cave of the volcano!

The Devil Banishers announce that they will judge Nero and Marie in public. Julius then orders the Black Bulls and other Magic Knights to go rescue them. The Magic Knights place themselves among a crowd that clearly hates the devil, and then the Devil Banishers appear. They then demand that the devil-possessed Asta show himself.

Though Vangeance, the Captain of the Golden Dawn, had asked Langris to return to his duties as vice captain, he continues to distance himself from the squad. Yuno had suddenly moved up all the ranks at a decoration ceremony and Langris asks him to fight him. The rest of the squad seems shocked, but Yuno accepts Langris’ request and fights him and they have a fierce battle. But during their fight, Yuno seems to have some doubts with how Langris is fighting.

Due to Nacht's spell, the Devil who has been granting Asta power since the beginning has appeared physically. To master his Devil powers, Asta must battle and defeat his Devil, and force him to submit. But Asta has other plans... Meanwhile, Yuno, Noelle, and the others grow stronger in order to take their revenge against the Dark Triad.