Kazumi Yumoto was born in Tokyo, Japan in 1959. She studied music composition at Tokyo College and during this time wrote opera libretti and plays for radio and television. Her books, mostly novels for older children, have won numerous international awards. After graduating from Tokyo National University of Fine Arts and Music, Komako Sakai worked at a kimono textile design company. She is currently one of the most popular children's author/illustrators in Japan, and has been successfully published in the US by Chronicle Books and Arthur A. Levine books.