Ichiya Kumagai is a 15-year-old aspiring film director driven by ambition to become Japan's top filmmaker. Typically reserved and shy, he transforms into a passionate and outspoken advocate when discussing movies or directing. His initial encounter with Mio Hagiwara involves blunt criticism of her acting, creating early friction. Despite this rocky start, he later approaches Mio to star in his debut feature film, recognizing her potential while maintaining his critical perspective on her performances.

Professionally, Ichiya directs a music video for pop idol Aya Sawaki, Mio's best friend, securing his first significant opportunity. This leads to funding for his feature film, where he casts Mio as the lead. Throughout production, his intense dedication to filmmaking often takes precedence over personal relationships. This single-minded focus causes him to initially reject Mio's romantic confession, refusing to acknowledge his own growing feelings.

Ichiya shares a complex history with Aya Sawaki, having been in a relationship before both moved to Hollywood at age 13. This past connection fuels complicated interpersonal dynamics. A serious accident during a dangerous motorcycle stunt for his film, resulting in a near-fatal fall from a cliff, forces him to confront and acknowledge his romantic feelings for Mio.

The narrative tracks his development from ages 15 to 17. Additional omake chapters depict him at age 25, continuing his filmmaking career. His journey shows an evolution from an emotionally reserved teenager fixated solely on professional goals towards someone capable of balancing personal relationships with artistic ambitions.