In Manchuria near the end of World War II, Kyoko Natsuki, the daughter of a respected physician, meets a young medical soldier named Hayami Kaori. The two are drawn to each other and fall in love, but their romance unfolds against a backdrop of mounting unease. When Japan surrenders, the war ends abruptly. Most soldiers are quickly withdrawn to Japan, but Kaori chooses to remain behind to help the remaining civilians. In the chaos of the postwar evacuation, Kyoko becomes pregnant with Kaori’s child. During the harrowing journey back to Japan, she suffers a miscarriage. Her teacher, Midorikawa, dies after giving birth to a baby girl on the ship, and Kyoko adopts the child, naming her Asuka—the name she had intended for her own child.

Once in Japan, Kyoko waits for Kaori’s return. He is captured by Soviet forces but eventually makes his way home, and the family is reunited. The story spans more than thirty years, following not only Kyoko and Kaori but also the lives of their daughters. Asuka grows up knowing she is not Kyoko’s biological child, which creates a quiet tension in the family. She becomes an excellent student, while her younger sister Mirai struggles with feelings of inferiority and acts out rebelliously. Asuka’s reserved nature and Mirai’s defiance are gradually reshaped by love and understanding. The narrative shifts to focus on Asuka’s own journey as she finds her place in the world and learns to move forward, embodying the story’s theme of shining tomorrow despite the weight of the past.