The story takes place in the early summer of Showa 21, when World War II had just ended and the land was devastated by the war. Okuhara Natsu (played by Hirose Suzu), who unfortunately became an orphan in the gunfire, was taken to Hokkaido by the kind-hearted Shibata (played by Fujiki Naoto). Shibata was a comrade-in-arms of Koxia's father. They had made an agreement that if one party died in the war, the other party would take the responsibility of taking care of the other's family. In this way, Koxia began to live under the protection of others. Shibata's father was a man with a hard mouth and a soft heart. Although he said that Koxia was an unlucky child, he still took care of her in life. By chance, Koxia met a boy named Yamada Chengyang. His extraordinary painting skills deeply attracted Koxia and opened the door to a new world for her. Koxia began to have a strong interest in painting.