Kimura was born in Tokyo and graduated from Tama Art University. He began working in arts education before transitioning to become a creative director for children's television programming. Eventually, he shifted his focus to writing picture books and stories. One of his works, Arashi no Yoru ni (One Stormy Night), earned him several awards including The Kodansha Award for Picture Books and the JR Award for Children's Books & Publications - Junior Category. Kimura also adapted this work into a stage play, where it received additional recognition. In 2005, an animated film adaptation of "One Stormy Night" won the Japan Academy Award in its category. With over 500 literary works to his name, many of which are long-time bestsellers, Kimura has made significant contributions to Japanese literature. Other notable works include "Wings of Flight" and "Hungry Diary of Gonnosuke, the Wolf".