Nao Kamiya is a seventeen-year-old idol from Kanagawa Prefecture who appears in The IDOLM@STER Cinderella Girls: Spin-off!. She has long brown hair, red eyes, and a height of 154 centimeters. She is a Cool-type idol known for her tsundere personality. Nao finds it difficult to express her true feelings and often hides her shyness behind sharp words and defensive reactions, becoming flustered when her walls are breached. This behavior stems partly from her upbringing, where her family bought her boyish clothes rather than cute ones, leaving her insecure about appearing feminine. Despite this, she secretly wishes to be more girly and to be seen as cute, though she frequently denies the possibility.

Her motivations center on overcoming her own doubts and becoming a capable idol. She initially believed becoming an idol was impossible for someone like her, but she works hard to improve and takes her career seriously. In the spin-off, she is one of four idols who suddenly appear at a wedding ceremony and whisk the bride away, leading to a chaotic car chase and running gun battle. Her role in the story is as a member of this impulsive group, contributing to the comedic action.

Nao maintains close friendships with fellow idols Rin Shibuya and Karen Hojo, though her tsundere nature complicates these relationships. She often shows warmth and approval indirectly, through contradictory statements rather than direct praise. She also serves as a mentor and leader figure for other idols, particularly in the unit NEX-US, where she is well-regarded despite being the constant target of teasing due to her prickly reactions. Her development is marked by a gradual increase in confidence, both in her idol abilities and in allowing herself to embrace cute or feminine expressions, even as her core tsundere traits remain. Notable abilities include her singing and dancing, typical of a Cool-type idol, and her knack for taking on a leadership role when needed.