Takayuki Narumi drifts through high school with no clear ambitions, maintaining a casual indifference toward academics and the future. His first meeting with Haruka Suzumiya at a bookstore blossoms into tentative affection after mutual friend Mitsuki Hayase bridges their connection during their third year. Inspired by Haruka, he tentatively embraces higher education aspirations until a fateful decision to prioritize Mitsuki’s birthday over a critical meeting with Haruka leads to a catastrophic accident, leaving her comatose.

Consumed by remorse, Takayuki abandons his studies and retreats from society, surviving through menial work at a family restaurant. Mitsuki becomes his emotional anchor, their bond deepening into a fragile romance sustained through three years of shared instability.

Haruka’s sudden awakening—unaware of the elapsed years due to anterograde amnesia—forces Takayuki and Mitsuki into a web of concealment to shield her fractured psyche. This deception fuels resentment from Haruka’s sister Akane, who views their secrecy as betrayal. Caught between obligations to Mitsuki and unresolved feelings for Haruka, Takayuki battles paralyzing indecision amidst societal judgment and self-reproach.

Branching narratives in the source material explore alternate romantic possibilities with coworkers Ayu Daikuuji and Mayu Tamano, though the core story remains anchored in the Haruka-Mitsuki dilemma. While the anime adaptation concludes with Takayuki recommitting to Mitsuki despite uncertain prospects, an OVA epilogue revisits the timeline to envision reconciliation with Haruka—a resolution that diminishes Mitsuki’s emotional sacrifices.

Across all iterations, Takayuki’s journey maps the corrosive effects of trauma and the halting path toward self-forgiveness, illustrating how indecision fractures lives and dependency shapes identities.