Iolite, once the youngest Platinum Square magician in history and celebrated as the "Greatest Genius of the Magical World," had his rank revoked after stealing power from the entity Gannet Granatus, known as "the God." Though fallen from grace, his ambitions and magical skill remain undiminished.

He is a young man with dark green hair and distinctive, space-themed eyes, typically dressed in a sleeveless top, shorts attached to stocking boots, and a hooded cloak.

Mischievous, lazy, sadistic, and psychopathic, Iolite often displays childish and bratty behavior when interrupted or challenged. He shows severe intolerance for failure, readily disposing of those he deems weak, like his former pawn Obsidian. Highly manipulative, cunning, and ruthless, he kills without hesitation, even children. Yet he exhibits childlike enjoyment in eating lollipops and playing Shogi with his collaborator Kohakumiya, though he grows bored from constant victory. He is highly intelligent, confident, methodical, and unwaveringly determined.

As a former Platinum Square magician, Iolite wields vast magical power and stands among the most skilled magic users alive. He summons a giant, highly durable stone golem resembling a castle, impervious to many magics and capable of summoning powerful cannons. He is also rumored to have stolen the ability to create life. His genius-level intellect allows him to complete complex magical exams in seconds, achieving perfect scores from bronze to gold, including practical assessments.

Iolite serves as a main antagonist and archenemy to Alto Goldfield and his familiar, the demon Vermeil. Motivated by a desire to claim Vermeil’s power and regain his lost status, he infiltrates Ortigia Academy of Magic by murdering a student from a neighboring school during the Bronze Exams to confront them directly. After a battle where he is forced to retreat due to interference from his associate Heliodol, he warns Alto that he will return to kill him and everyone he cares about.

He collaborates with Kohakumiya, playing Shogi with her despite finding it tedious, and associates with Heliodol, though he dislikes her interruptions. He manipulated Obsidian, Alto’s disgraced former mentor, into performing experiments, but deemed him worthless after failure. His central adversarial relationship is with Alto Goldfield, whom he views as his archnemesis.

In his chronology, Iolite kills a priest and bishops who were Platinum mages before heading to the academy. There, he battles Alto and Vermeil, retreating temporarily, with his pursuit of power and conflict ongoing.