Okuhara Natsu was born in Tokyo in 1937. In 1945, she loses both parents to war and becomes an orphan, but her father’s comrade, Shibata Takeo, takes her in and moves to Tokachi in Hokkaido. In an unfamiliar land surrounded by unfamiliar people, Natsu feels lost at first, but surrounded by Tokachi’s vast nature and its strong, yet compassionate people, she grows up to be a strong girl. When Natsu enters elementary school, she meets Yamada Tenyo who draws lovely pictures of horses. Tenyo tells her that in America, animation in which pictures move is becoming popular, Natsu’s curiosity is piqued. Upon graduating high school, Natsu goes to Tokyo to look up her brother, and takes a jump into the world of animation.