Yukio Kunikida and Yuma Yamagishi are high school students and they are dating with each other. On an ordinary day, Yuma tells Yukio that "I'm going to die in a week." She knows that her illness has progressed and has accepted the fact that her days are numbered. She wants to live the rest of her days being true to herself. Yukio finds it difficult to accept that Yuma has just a short time left to live, but he occupies himself fulfilling her wishes.