Daisuke Hiyama

Occupation: Light Warrior

A leader among delinquents. He takes pleasure in tormenting those weaker than himself, while groveling to those stronger, revealing his cowardly nature.

He harbors a twisted affection for Kaori. He resents Hajime, who receives attention from her, and has been harassing Hajime along with Nakano, Saito, and Kondo since their time on Earth. After being summoned to another world, he continued to look down on the "incompetent" Hajime, bullying him under the guise of special training with the other three. His hatred intensified when he witnessed Kaori entering Hajime's room the night before their expedition to the Great Orcus Labyrinth.

In the Great Orcus Labyrinth, his reckless actions lead to the appearance of a Behemoth. While his classmates were casting magic at the Behemoth to save Hajime, who was acting as a decoy, he took advantage of the chaos to cast a fireball at Hajime, causing him to fall into the abyss. However, that night, overwhelmed by guilt for having caused Hajime to fall, he desperately tried to justify his actions to himself, only to be seen by Eri. She blackmailed him into compliance by threatening to expose him, but offered to give him Kaori in return, which he accepted.

He was shocked to find Hajime alive during the battle with Cattleya and desperately tried to stop Kaori from following Hajime. Realizing that Hajime knew about the fireball, he reluctantly gave up under implicit threats. Later, fueled by resentment towards Hajime for "stealing" Kaori and realizing that their powers had completely reversed, he almost gave up on Kaori but was persuaded by Eri to reignite his obsession with her, continuing their alliance and secretly turning knights into puppet soldiers. In the book version, he also stabs Meld in a surprise attack with a dagger, but Meld escapes without a fatal wound (in the anime, he is seriously injured).

During the invasion of the royal capital, he conspired with Eri to pretend to be severely injured, then stabbed Kaori from behind when she came to help, attempting to kill her and turn her into his puppet using Eri's necromancy. However, an enraged Hajime beat him thoroughly.

Despite being severely injured, he attacked Hajime with intense vengeance for taking Kaori, but was scorned as a "born loser who only complains about others and can't bear anything himself, only capable of flattering the strong." In the end, he was thrown into a swarm of invading monsters. As if to atone for the sin of causing Hajime to fall and lose his left arm, he was eaten alive, his left arm torn off first, and he died unable to escape as his body was devoured.