The Execution Division Apprentice is typically seen wearing a white military-style uniform, consisting of a fitted jacket and a matching skirt, paired with black tights, red socks, and black combat boots. Her outfit is completed with a red belt, from which she carries her standard-issue energy sword, a signature weapon of the Execution Division. She has short black hair, sharp red eyes, and a youthful yet determined appearance that reflects her status as a trainee.

In Episode 6, she sustains a serious injury during battle, resulting in the loss of her right eye. A long scar runs vertically across the right side of her face, marking a significant change in both her appearance and character development. From that point forward, she wears a black eye patch to cover the injury.

By Episode 11, the Apprentice’s uniform undergoes a transformation to reflect her growing experience. She adopts the attire of a full-fledged Executioner, now featuring red shoulder pads and cuffs elements associated with higher-ranking members of the division. Additionally, she replaces her skirt with trousers, signifying her shift from a subordinate apprentice to a more authoritative figure.

The Execution Division Apprentice is a serious, disciplined, and duty-bound individual, deeply committed to her role in eliminating Akudama. Her unwavering work ethic earns her the codename “Full Effort”, reflecting her intense dedication to carrying out her responsibilities. She demonstrates strong respect for her superiors, particularly her mentor, the Execution Division Master, and often displays visible enthusiasm when he suggests intensifying their efforts. While loyal to her orders, she is not without initiative; she is willing to propose bending or defying commands if it means fulfilling what she believes is her true duty.

After suffering a major personal loss the death of her Master and the injury that cost her her right eye, Apprentice undergoes a notable transformation. She becomes more somber, detached, and cool-headed, choosing to work alone and distancing herself emotionally from others. Her superior, the Boss, observes that this change is rooted not in independence but in a subconscious death wish, as she increasingly takes dangerous tasks upon herself. Despite claiming she no longer needs a partner, she remains courteous and protective toward her Junior, reassuring him that he need not fight because she intends to shoulder the risk herself. This eventually reveals her underlying fear of losing another comrade.

Though she maintains a strong belief that killing Akudama is a matter of pride, her rigid conviction begins to soften. In Episode 10, she hesitates to kill Swindler and Hoodlum despite both being criminals and the latter being responsible for her injury. This moment of indecision suggests a growing conflict between her moral compass and her official duty, revealing emotional complexity beneath her disciplined exterior.

The Apprentice is a young officer in the Kansai Police Execution Division, known for her intense determination to eliminate Akudama. While she is ambitious and eager to prove herself, her drive occasionally outpaces her actual abilities, leading to moments of vulnerability. She holds deep admiration for her mentor, the Execution Division Master, whom she looks up to as a role model and guide.

She had been partnered with the Master for approximately two years, gradually approaching the point of operating independently. Her assignment to pursue the Akudama who freed Cutthroat was intended to be her final mission as an apprentice, but it would become a pivotal turning point in her life. During a confrontation on the Shinkansen, both she and her Master sustained injuries and were hospitalized. Unbeknownst to her, the Master later left the hospital alone to confront the Akudama once more ultimately leading to his death at the hands of Brawler.

Refusing to remain idle, Apprentice searched relentlessly for her mentor despite being denied assistance from her superiors. She arrived at the scene too late, only to witness his final moments. While still in shock, she was attacked by Hoodlum, who struck her in the eye, leaving her permanently scarred.

The combined trauma of losing her mentor and sustaining a disfiguring injury prompted a significant change in her outlook. Though she claimed she no longer needed a partner and requested to work alone, she was nonetheless assigned to mentor the Execution Division Junior. While initially resistant, this new partnership becomes a subtle reflection of her evolving mindset as she grapples with loss, duty, and personal growth.

The Execution Division Apprentice is a highly skilled martial artist, specializing in hand-to-hand combat and close-quarters engagement. Her agility, precision, and reflexes allow her to react instantaneously to threats, such as sensing an enemy’s approach or deflecting projectiles mid-air. In terms of combat prowess, she has shown herself to be capable of holding her own against formidable opponents, including Brawler, one of the physically strongest Akudama, suggesting a level of physical discipline and tactical instinct well beyond standard law enforcement training.

Despite her strengths, she is not yet on par with the Execution Division Master, her mentor, and still has room for growth. Her technique and reaction time are impressive, but her experience and strategic depth are still developing, as acknowledged within the series.

In Episode 12, Apprentice demonstrates her quick reflexes and composure under pressure during a confrontation with Courier. She becomes the only Executioner to survive a direct attack from him, successfully blocking a bullet using her energy sword with remarkable speed. This moment highlights her ability to remain alert and composed even in high-stakes, life-threatening encounters.