Kyōsuke Tsurumaki is a central character in the story, introduced as a 22-year-old freeter living at home. His background is deeply rooted in music; he met his close friend Kai Amano in high school, and together they formed a musical duo named Kanitama. The duo was on the verge of making their major debut when Kai was killed in a traffic accident.

This tragic event profoundly affects Kyōsuke, shaping his personality at the start of the narrative. Overcome by grief and disillusionment, he quits music entirely. He becomes a freeter, taking on part-time jobs without direction or passion, and lives a life devoid of the creative ambition that once defined him.

His motivation undergoes a dramatic shift when Kai suddenly reappears before him, seemingly alive and embodying the energetic spirit of his past self. This unexpected encounter rekindles Kyōsuke’s passion for music. The reappearance of his deceased friend serves as the catalyst for Kyōsuke to abandon his withdrawn lifestyle and restart his music career.

In the story, Kyōsuke’s role is that of a reluctant protagonist whose journey is centered on overcoming trauma and rediscovering his purpose. His most significant relationship is with Kai Amano, his former musical partner. Kai’s death is the source of Kyōsuke’s pain, and his mysterious return is the key to Kyōsuke’s potential recovery and return to music.

Throughout the narrative, Kyōsuke experiences notable development, transitioning from a disillusioned young man who has abandoned his dreams to someone who decides to face his past and embrace music once more. His primary notable ability is his musical talent, specifically his skills as a musician that allowed him to form a promising duo with Kai before his life was interrupted by tragedy.