Monaka Yatogame is a 16-year-old first-year student at Tagane High School in Nagoya, Aichi Prefecture. Raised primarily by her grandmother, she developed a strong connection to local traditions and culture. Her distinctive blonde hair is styled to resemble cat ears, and she often displays cat-like mannerisms during social interactions.

Monaka speaks with a pronounced Nagoya dialect, initially feeling self-conscious about it but fiercely embracing it when defending Nagoya's cultural identity. Her regional pride fuels defensiveness toward outsiders, especially those from Tokyo who disregard local customs. She actively monitors and corrects perceived cultural dismissals, serving as an informal ambassador for Nagoya's heritage.

Her familial ties include a cousin, Shiharu Itemae, who calls her "Mona-nee"—a nickname Monaka dislikes. Their dynamic implies a protective or mentoring role she fulfills despite resisting the label.

Monaka's development revolves around her evolving relationship with Kaito Jin, a Tokyo transplant joining her photography club. Initially distant and wary of his outsider perspective, she gradually engages as he shows genuine interest in Nagoya. Her interactions shift from guarded resistance to reluctant guidance, using club activities to introduce local landmarks, food specialties like miso katsu and tebasaki chicken wings, and linguistic nuances. This progression reflects growing tolerance and a subtle willingness to bridge cultural gaps, though her unwavering advocacy for Nagoya remains central.