Dantalion Dali A teacher at Babyls Academy for Demons. Chief of the faculty. He is always smiling. He loves interesting things. He gets carried away with jokes easily. He is a veteran who has been at Babyls for a long time.

Murmur Tsumuru Male. A teacher at Babyls Academy for Demons. Mental magic specialist. The "sane" one of the group. His tone becomes blunt and rough when speaking to his colleagues.

Ipos Icho Male. A teacher at Babyls Academy for Demons. He looks serious but actually joins in on jokes readily. His tone becomes blunt when speaking to his colleagues.

Ifrit Jin Eight Male. A teacher at Babyls Academy for Demons. Security officer. The "sane" one of the group. Gentle with students. His tone becomes blunt when speaking to his colleagues.

Iruma Suzuki Rank: Daleth (4) Male. Member of the Abnormal Class. An extremely kind-hearted and helpful boy. Sold to the Netherworld by his foolish parents, he became the grandson of the great demon Sullivan. He attends Babyls while hiding his human identity. He is so close with Asmodeus and Clara that they are known as the "Iruma Trio."

Asmodeus Alice Rank: Daleth (4) Male. Member of the Abnormal Class. An elite demon who was the top student in the entrance exam, specializing in fire magic. Since the entrance ceremony, he has sworn loyalty to Iruma and accompanies him everywhere as an irreplaceable friend. Coming from a family that governs destruction and virtue, he possesses a noble demeanor that values etiquette, but he shows a completely different, devoted side when it comes to Iruma.

Valac Clara Rank: Gimmel (3) Female. Member of the Abnormal Class. A cheerful and energetic girl demon who is also restless and noisy. Moved by Iruma's kindness, they became dear friends. She is very close with her family and has five younger siblings. She loves her friends Iruma and Asmodeus.

The Chair-Demon of Babyls Academy and one of the "Three Heroes," the high-ranking demons considered closest to being the next Demon King. He is the one who brought Iruma to the Netherworld. He dotes on his first grandson, Iruma, to an extreme degree while warmly watching over his growth.

Naberius Kalego A very strict teacher at Babyls Academy. Homeroom teacher of the Abnormal Class. His catchphrase is "Silence." He is not good at dealing with Sullivan.