Kuninao Utagawa is a teenage artist from the prominent Utagawa painting school in Edo-period Japan. He regularly visits Katsushika Hokusai's studio, interacting with both Hokusai and his daughter O-Ei. These visits place him within Hokusai's artistic circle, demonstrating his professional ambitions and connections in the ukiyo-e community.

Kuninao possesses an extroverted personality but shows awkwardness in unexpected situations. He develops unresolved romantic feelings for O-Ei. Their dynamic shifts when O-Ei observes him with another woman during an outing, causing her to abandon romantic interest. This incident highlights the unreciprocated or complicated nature of their relationship.

The narrative does not show significant personal growth or artistic evolution for Kuninao. His role primarily illuminates aspects of O-Ei's life, particularly her ambivalence toward conventional relationships and her focus on artistic pursuits. Kuninao's presence reinforces the story's slice-of-life structure, contributing to its episodic depiction of daily experiences in Edo.