It is the last day of Isla's lifespan and she and Tsukasa decide to first spend it by reading entries in her diary. They then spend the morning cleaning up their dormitory room and then taking a bath. They then head over to the office, where they take care of Isla's herbs and she leaves notes for the other employees. They are approached by an early Kazuki, who teases Isla for one last time. The two then decide to spend the day's remaining hours at the amusement park, which they enjoy to their hearts' content. Eventually, they stand at Isla's favorite bench, where she describes how she always observed the emotions of the park's many visitors and how contented they would be at the end of the day in bringing their happy memories home with them. Then, as the park closes, Tsukasa and Isla convince the operator to let them ride the Ferris wheel one last time after closing hours. There, they take turns describing what they love about each other, and Isla finally admits she loved the way Tsukasa held back his sadness and smiled, despite her worry over that characteristic. She then hands him her deactivation ring, saying that she wanted him to be the one to do it. Tsukasa begins crying, and Isla notes that it was the first time she ever saw him cry. He then puts the ring on, expresses his hope that she would be reunited with the person they cherished, and kisses Isla as her time expires. As he carries her to the vehicle, he is met by Kazuki, who thanks him for being there for her, which causes him to break down in tears. The other Terminal Service employees read Isla's letters, in which she thanks them for all the memories she had of them.
In the epilogue, Tsukasa takes the same elevator where he met Isla and muses what it would be like if his lifespan was predetermined, concluding afterward that he would live that life to the fullest. Nine months later, he returns from a training course to resume work with Terminal Service No. 1, and is introduced to his new Giftia.