Love Unseen Beneath the Clear Night Sky

After learning that Koharu, who had been out of contact, is in the hospital, Kakeru, Narumi, and Yuko rush to see her. In the hospital’s kids’ room, Kakeru finds Koharu playing the piano for children. When he speaks to her, she responds with, “Who are you?” and rejects him. From Koharu’s mother, Haruka, they learn that Koharu’s memory has become confused due to a certain reason, leaving them in shock. Meanwhile, Koharu spends her days volunteering in the hospital's kids’ room, playing the piano for the children. One day, determined to spend more time with Koharu even if she cannot remember him, Kakeru takes action. However, he soon learns that Koharu has been suffering under a reality far more painful than he ever imagined.

Koharu tells Kakeru that she has only six months left to live and asks him to forget about her, saying goodbye. Faced with this sudden and harsh reality, Kakeru cannot find an answer for what he should do. Narumi and Yuko find a flyer for a fireworks festival to be held after the New Year, hoping to do something for Koharu, who loves fireworks. Still, Kakeru remains lost, unsure of what the right choice is. Meanwhile, Koharu, not wanting to cause pain to the people she loves, begins to consider giving up on treatment altogether. At that moment, Kakeru remembers Koharu’s “yellow bookmark” and realizes that the “Things I Want to Do” list written on it is not finished yet. Once again, he starts running forward for Koharu’s sake.

Koharu, who promised Kakeru that she would go to the New Year fireworks festival with him, continues her rehabilitation with all her strength. At the same time, Kakeru struggles with doubt, wondering whether pushing Koharu forward when recovery seems unlikely might be irresponsible. One day, Kakeru is approached at the hospital by Miura, Koharu’s attending physician. He opens up about his uncertainty, and after hearing Miura’s words, Kakeru decides to stay by Koharu’s side no matter what. Meanwhile, Koharu works hard at her rehabilitation with the fireworks festival in mind, but feelings of anxiety and resignation begin to take root deep in her heart. One night, she lets her true feelings slip while talking to Yuko. As the fireworks festival approaches, Koharu, Kakeru, Narumi, and Yuko support one another while carrying their own feelings.

On the long-awaited day of the fireworks festival, Koharu’s condition suddenly worsens and she collapses. Thankfully, she regains consciousness. Despite having worked so desperately through rehabilitation for the sake of the festival, Koharu is devastated when she realizes she cannot go. Seeing this, Kakeru, with the help of Narumi and Yuko, carries out a certain plan in Koharu’s hospital room. It becomes a moment that feels almost miraculous. In that room, Koharu tells Kakeru for the first time another reason why she loves fireworks, one she had never shared before. Even if sight is lost, even if memories fade, the two believe that some things remain for certain. Holding onto that belief, Koharu and Kakeru move forward, wondering what kind of path lies ahead for them.