Rank: Daleth (4) Male Member of the Misfit (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 the demon school Babyls while hiding his identity as a human. He is so close to Asmodeus and Clara that they are collectively known as the "Iruma Army."

Guest's younger brother. Rank: Daleth (4) Male Member of the Misfit (Abnormal) Class. A top-tier honor student who excelled in the entrance exams and specializes in fire magic. Since the entrance ceremony, he has sworn loyalty to Iruma and accompanies him everywhere, becoming an irreplaceable "soulmate." Coming from a lineage that governs destruction and virtue, he possesses a noble air and values etiquette, but when it comes to Iruma, he shows a level of devotion that makes him seem like a different person. He deeply respects and loves his older sibling, Guest.

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

The Chair-Demon of Babyls and one of the "Three Greats," the high-ranking demons considered closest to becoming the next Demon King. 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.

Sullivan's excellent butler. They handle everything from housework to security perfectly. Generally stoic, but they watch over Iruma and provide accurate, sincere advice when he is in trouble. They have cat-like ears and a tail, with red hair tied in a braid.