Naoko Naruse is a main character with light brown hair and blue eyes, exhibiting a tomboyish personality. Her surname Naruse combines "become" (成) and "swift current" (瀬), while her given name Naoko means "straight, direct" (直) and "child" (子). She attends Oribe Gakuen high school.

Within the pottery club, Naoko works alongside Himeno Toyokawa, Mika Kukuri, and Toko Aoki. During the second season's cultural festival, she participates in class activities with them. When Himeno faces creative pressure over a display spot reserved by her father, Naoko suggests crafting mugs tailored to individual users. This inspires Himeno to experiment with diverse designs based on each recipient's traits, resulting in personalized creations.

Naoko created the mascot character Rokurō. This mascot later became the protagonist of the spin-off ONA "Rokurō no Dai Bōken," where it assists dentists and dental hygienists while promoting dietary information to prevent dental diseases. Within this spin-off's narrative, Naoko is credited as Rokurō's original creator.

Her interactions include informing Toko Aoki about Himeno's challenges, which prompts Toko to share her own experiences with overcoming artistic expectations. Naoko also takes part in radio program segments and location shoots in Tajimi, including visits to local cafes and pottery shops.