Airi Hayashida is a 15-year-old high school freshman and founding member of the idol group Wake Up, Girls!. She sports light-brown neck-length hair, blue eyes, and a distinctive mole on her left cheek, typically dressing in long-sleeved shirts or jumpers with skirts.

Starting without professional skills, Airi compensates through persistent hard work and unwavering dedication. She often battles nervousness and self-doubt about her abilities compared to the others, frequently needing encouragement from fellow members Mayu Shimada and Yoshino Nanase. Her supportive and nurturing nature leads the group to embrace her as a maternal figure, as she consistently looks out for their well-being. Her background includes working at her family's sweets store.

Airi's journey faces a critical challenge when producer Tasuku Hayasaka nearly removes her from the group due to perceived insufficient improvement. This decision is reversed following interventions by Mayu and Yoshino advocating for her, coupled with collective appeals from the entire group to Hayasaka. Afterwards, her performance level steadily rises to match the other members through sustained practice.

Across subsequent media, including the Idol Festival arc and the "New Chapter" storyline, Airi remains integral to the group's collaborative efforts, participating in nationwide tours and contributing to lyric-writing sessions for new songs like "Polaris," demonstrating her ongoing development as a performer and creator. Her image color is indigo and her associated animal motif is a shark.