Shinohara Tooru was born in Niihama, Ehime. After graduating from high school on March 1955, he started working at a factory in Osaka making car parts but quit after only ten months. He studied manga via a mail-offered course and wrote to various manga magazines. In 1958 came his first commercially printed work Fukumenhakushi (覆面博士) and he began his career as a manga artist.
He is best known for Nippon Keibaden that detailed the history of Japan's horse racing industry and its horses. He is also known for beautiful amazon-like heroines who are never daunted by the hardship they endure. Since 1970, he has written a series of works titled Sasori, lit. scorpion, which is the name for a female inmate and heroine. Director Shunya Ito started a series of ten films starring Meiko Kaji based on the manga. However, Ito withdrew from the project after three, and Kaji four films. Many of his works have been turned into movies since 1972.