Yôko Matsunaga coaches the Nikko Dream Monkeys women's ice hockey team, driven by the goal of boosting hockey's popularity in Japan. She pursues this through an unconventional strategy merging athletic competition with idol culture, envisioning packed arenas for both hockey games and synchronized dance routines. Her own background as a former player informs her coaching philosophy.

Her recruitment tactics showcase persistence, notably convincing talented player Yu Kiyose to join the Dream Monkeys after Yu quit a rival team. Matsunaga deliberately left a pen at Yu's residence to ensure a return visit to the rink, anticipating that seeing practice would reignite Yu's passion—a strategy that succeeded.

Matsunaga incorporates unique elements into her coaching. She introduced specialized warm-up exercises readily adopted by senior members but not shown to be used by junior players. During training, she advised goaltender Kaoruko Yanagida to improve on-ice communication, stressing verbal coordination's importance for teamwork. To reinforce this lesson, she organized a beach volleyball outing where Kaoruko's initial silence contributed to mounting losses, indirectly teaching the value of clear communication during gameplay.

Physically, Matsunaga possesses auburn hair and golden eyes. Her appearance during television interviews featured noticeably heavy makeup, drawing comparisons from observers to theatrical or clownish styles. She works alongside assistant coach Sou Sato, who often reacts with deadpan commentary to her enthusiastic, sometimes eccentric ideas about blending hockey and entertainment; she proceeds undeterred by his skepticism. Her birthday is April 5th.

No substantial character evolution or expanded backstory across additional media formats is documented.