Miyuri Chaser is the younger sister of Raul Chaser. Before departing their hometown, Raul promised Miyuri he would return only after becoming a hero, dedicating himself fully to that goal. Miyuri learned of the hero program's cancellation yet maintained unwavering belief in her brother's vow. She fiercely defended him against accusations of failure or abandonment. Despite Raul's extended absence and silence, she eagerly anticipated their reunion during her trip to the capital.

To protect Miyuri's idealized vision of him as a triumphant hero, Raul enlisted friends in an elaborate deception. He could not bear to reveal his mundane magic shop job. This staged demonstration suffered multiple mishaps and inconsistencies, but Miyuri's absolute trust in her brother caused her to overlook the flaws. The situation spiraled out of control, compelling Raul to act with genuine heroism to save her.

During this critical event, Raul discovered Miyuri possessed immense latent magical power. Her previously unknown abilities exploded into reality under duress, unveiling a major facet of her character. This ordeal gave Raul new insight into Miyuri's capabilities and their bond, while Miyuri gained a more complex understanding of her brother's situation—though her fundamental admiration remained intact.