Hiro Hirono, a 17-year-old high school student, balances life as a professional shōjo mangaka under the pseudonym “Nagi Shindou”—a fusion of his sister Nagi’s name and childhood friend Kei Shindou’s surname. Prioritizing manga over school, his frequent absences strain academics and friendships, while relentless drawing exacerbates chronic tendonitis in his dominant arm, jeopardizing his career. Nagi intervenes, aiding with inking and lettering to reduce his physical burden.

Hiro navigates a turbulent love triangle between Kei, who quietly tends to his daily needs while concealing her feelings, and Miyako Miyamura, a bold classmate who sparks his interest after impulsively stealing his bike during a theft. Miyako’s assertive pursuit clashes with Kei’s unspoken devotion, escalating tension until Hiro reluctantly commits to Miyako, sharing three kisses and an implied deeper intimacy.

His chronic indecisiveness—criticized by peers like Kyosuke Tsutsumi, who confronts him violently—extends to fears of abandoning manga due to deteriorating health. The narrative charts his hesitant growth: accepting Nagi’s support, solidifying his bond with Miyako, and tentatively confronting career uncertainties. Though still grappling with doubt, Hiro begins embracing reliance on others, signaling a fragile shift toward decisiveness.

Living alone, Hiro’s solitude is punctuated by Kei’s unwavering care and Miyako’s dynamic presence. Their contrasting influences—Kei’s quiet devotion versus Miyako’s forthright passion—mirror his internal struggle between passivity and action. While his choice of Miyako marks progress, unresolved questions about his manga future linger, underscoring a journey of incremental self-discovery amid artistic and emotional turbulence.