Nice possesses disheveled auburn hair, blue eyes, and pale skin. He consistently wears unexplained white bandages across his nose, cheeks, and arms. His typical attire features distinctive green/yellow headphones around his neck, a blue shirt with a jacket vest, black pants with a white belt, and blue-and-red shoes.

He exhibits an empathetic yet carefree personality, often prioritizing others' well-being over payment during detective work. Despite his generally positive demeanor, Nice displays occasional bluntness perceived as condescending and demonstrates absent-minded tendencies, like attempting bank transactions during an active robbery. He rejects conventional heroic ideals, confronting the antagonist Moral solely out of personal annoyance rather than moral obligation.

As a former top student at Facultas Academy, Nice possessed exceptional talent as a Minimum Holder. He abandoned his studies to search for Hajime, a fellow student subjected to experimental research labeled "Success Number 01." During their escape, Nice sustained a gunshot wound to the heart, surviving only through an emergency transplant of Skill's heart—a procedure orchestrated by Moral. This granted Nice two distinct Minimum abilities, a physiological impossibility for ordinary Minimum Holders.

His primary ability, Sonic Minimum (Cannon Ball Minimum in manga sources), requires his headphones and a finger snap to activate. This allows transformation into sound waves for supersonic movement and attacks, limited to audible sound distances and requiring repeated snaps for sustained use. His secondary ability, Ego Minimum, stems from Skill's transplanted heart. Manifesting as a yellow light dome, it restores lost Minimum powers or egos—directly countering Hajime's Nihilist Minimum. This ability activates through feelings of hope and remains largely dormant until critical moments.

Key relationships define his journey:
* **Art**: Childhood friends turned adversaries after Art's apparent death and subsequent leadership of the anti-Minimum group Freemum. Nice pursues Art following his descent into violence, seeking to "beat him up for making himself cry" after tragic events.
* **Hajime**: Shares a profound bond stemming from rescuing her from Facultas. He named her "Hajime" to replace her experimental designation. She demonstrates unique trust toward him, such as sharing food—a significant gesture given her typically possessive attitude toward meals. Their abilities are intrinsically opposed, with Hajime's despair-triggered Nihilist Minimum negating powers while Nice's Ego Minimum restores them.
* **Murasaki**: Initially rivals at Facultas, they evolve into detective partners. Murasaki exhibits fierce protectiveness toward Nice, while Nice displays tsundere-like behavior toward him.

In the spin-off *Mini Hama: Minimum Hamatora*, Nice appears in a comedic super-deformed format.