Sato serves as assistant to Yoko Matsunaga, coach of the Nikko Dream Monkeys girls' ice hockey team, supporting her unconventional efforts to boost the sport's popularity—such as merging ice hockey with idol performances. He manages Yoko's varied schemes and handles team logistics.

Patient and accommodating, Sato responds to Yoko's unpredictable or demanding initiatives with steady composure. His deadpan reactions to her eccentric ideas position him as the straight man to her flamboyant personality. Sato's background includes student theater participation, where he adopted the self-proclaimed title "Jim Carrey of Kirifuri," reflecting his comedic acting aspirations. This theatrical experience occasionally surfaces in team interactions, like when he deliberately overacted while pretending not to recognize Yu Kiyose during a rink visit. His intentionally unconvincing yet purposeful performance encouraged Yu to engage with the team.

Throughout the series, Sato maintains a consistent supportive presence during team activities, practices, and games. His role focuses strictly on operational support, excluding direct coaching or player development. No significant character evolution or background expansion beyond his position as Yoko's assistant occurs.