Ikki Kajiwara was a Japanese author, manga writer, and film producer whose work defined the sports and martial arts genres in manga and anime. Born Asaki Takamori on September 4, 1936, in Tokyo, he later adopted the pen names Ikki Kajiwara and Asao Takamori to write for rival publications simultaneously during his early career.

Kajiwara’s background heavily influenced his creative identity. The son of an illustrator and editor, he had a reputation as a juvenile delinquent with a strong interest in fighting in his youth. He began working as a novelist at the age of seventeen, which marked the start of his prolific writing career. Over the following decades, he became one of the most prominent manga writers in Japan, known for crafting stories centered on heroic young men in competitive sports and martial arts settings.

As the original creator behind numerous influential series, Kajiwara was responsible for the stories of many classic works. Among these are Kyojin no Hoshi (Star of the Giants), a baseball manga illustrated by Noboru Kawasaki; Akakichi no Eleven (Red-Blooded Eleven), a soccer manga illustrated by Mitsuyoshi Sonoda; and Judo Sanka (Judo Icchokusen), a judo manga illustrated by Shinji Nagashima. He also created Karate Baka Ichidai (Karate Master), illustrated by Jirō Tsunoda and Jōya Kagemaru, which focused on karate, and Kick no Oni, a kickboxing manga illustrated by Ken Nakajō. Other major credits include Ashita no Joe (Tomorrow's Joe), illustrated by Tetsuya Chiba, and Tiger Mask, illustrated by Naoki Tsuji, both of which became cultural touchstones. He often used the pen name Asao Takamori for some of these works, such as Ashita no Joe.

The adaptation history of Kajiwara’s works is extensive, as many of his manga were quickly adapted into popular anime television series and films. Kyojin no Hoshi, Akakichi no Eleven, Judo Sanka, Karate Master, and Kick no Oni were all adapted into television anime, with Kajiwara frequently credited as the original creator. He was also involved in film productions, serving as a supervisor or original creator for anime films based on his series, such as the Ashita no Joe movies and the Star of the Giants film. Beyond adaptations, he worked as a film producer on numerous martial arts documentaries and dramas throughout the 1970s.

Recurring themes in Kajiwara’s work center on intense physical competition, perseverance, and the pursuit of excellence in sports or martial arts. He is considered a key figure in establishing the hot-blooded sports manga genre, a field that major creators like Osamu Tezuka largely avoided. His stories often depicted determined young protagonists striving to become champions, frequently incorporating elements of real-life athletes and martial artists, such as the collaboration with Kyokushin Karate founder Masutatsu Oyama on Karate Baka Ichidai. Kajiwara himself considered Tiger Mask and Kyojin no Hoshi to be his life's work.

Kajiwara’s industry significance is marked by both his creative output and his later controversies. At the height of his career, he was known for writing multiple series simultaneously, managing up to five ongoing works at once, including Ashita no Joe. He received the Kodansha Manga Award twice: in 1967 for Kyojin no Hoshi and in 1975 for Ai to Makoto. However, his career was disrupted in the 1980s following legal issues, including an arrest for assault in 1983, which led to a suspended prison sentence and a decline in his public standing. He died from pancreatitis on January 21, 1987, at the age of 50. After his death, his work was critically re-evaluated, and his influence on later generations of manga artists and on the fighting game genre has been widely acknowledged.