Through his decades as a manga-ka, Shotaro Ishinomori had many assistants that had came and went, some branching off into their own successful careers later on while others opted to stay at Ishimori Productions and continue the legacy of some of his characters after his passing.
Duration as Assistant: 1965 to 1967
As Nagai would tell it, he had initially intended to be an assistant to Osamu Tezuka, but as he was out of town, he was given the opportunity to be the assistant of Ishinomori. While he enjoyed the time, he also found it difficult and challenging to keep up with the pace.
Duration as Assistant: Approximately 1965 to 1967
Takemiya's time under Ishinomori is not brought up as much as Nagai or other assistants, though it is known that she was considered one of his early star pupils as well. Like Nagai, she would soon start her own career shortly after her time as assistant.
Duration as Assistant: Unknown
The exact period of Ota's time as assistant is not as clear, although after his time with Ishinomori, he would then become an assistant for Go Nagai, working on an alternative manga of "Mazinger Z".
Eventually, Ota would also illustrate a gag manga version of Cyborg 009 The Movie: Legend of the Super Galaxy, released in 1981.
Duration as Assistant: 1969 through the 1970s
Sugaya is best known for his work on the TV Magazine version of the Kamen Rider manga, as well as adaptations of the sequels that ran in that magazine and Akita Shoten's Adventure King publication. He also illustrated the "First Grade" serialization of Kikaider.
Main article: Masato Hayase
Duration as Assistant: 1989 to 1990s, currently an artist for Ishimori Productions
Hayase is known for continuing the character designs for the Kamen Rider franchise after Ishinomori's death, and has contributed to chapters of the final Cyborg 009 story Conclusion GOD'S WAR, as well as illustrating the sequel and finale to the original Genma Taisen, titled "Genma Taisen Rebirth".
Duration as Assistant: 1972 to 1980s, illustrated other non-Ishinomori titles as well
Yamada worked as an assistant handling portions of Kikaider, as well as the TV Land version of Inazuman. He was one of the many artists to split time on the Gakken science learning manga Future Rescue Team Earth Guard 7 as well, illustrating the version for fourth grade science curriculum.
Duration as Assistant: 1971 to 1980s, also drew tie-ins for other Sentai manga
Hosoi mostly worked on Kamen Rider related manga, as well as Kikaider.
Duration as Assistant: 1970s
Became an assistant of Ishinomori in 1970 by association of Studio Zero.
Duration as assistant: 1976 to 1980s
Best known for illustrating Kamen Rider ZX in the 1982 Adventure King serialization.
Main article: Sugar Sato
Duration as assistant: 1970 to 1990s, currently an artist for Ishimori Productions
His prominent debut came around 1973 with his work on Inazuman, and he was a rather prolific assistant in his time. He illustrated the non-gag manga adaptation of Legend of the Super Galaxy and took over GOD'S WAR after Hayase left the project.
Duration as assistant: 1972 to 1982
Illustrated a version of Kamen Rider for Kodansha's Fun Kindergarten magazine, as well as manga for the sequel series in Adventure King and TV Magazine. He also illustrated the "First Grade" serialization of Inazuman.
Main article: Yoshiki Tsuchiyama
Duration as assistant: 1972 to 1980
Illustrated Henshin Ninja Arashi for TV Magazine, and was another artist for Kikaider. He also worked on Future Rescue Team Earth Guard 7.
Duration as assistant: 1975 to 1976
Real name: Makoto Kanno.
Also worked as an assistant for Go Nagai, for the TV Land version of Mazinger Z and Steel Jeeg. He worked on Future Rescue Team Earth Guard 7.
Duration as assistant: 1981 to 1982
He is known for his time at the company having been brief before his own career took off. Sadly, this would be a short-lived success as he would be found dead in his apartment on August 9, 1984 at the age of 26.
Though different opinions aroused as to his exact cause of death, and it was believed he suffered hypothermia due to having an air conditioner running while not dried off, the common assumption is that this death came due to overworking himself.
Duration as assistant: Unknown
Real name: Mariko Ogawa.
A shoujo manga-ka who began her career in 1969, writing several series that ran in the Margaret shoujo magazine. Her exact contributions with Ishinomori are not stated in detail.
Duration as assistant: 1975 to 1990
Illustrated additional Kamen Rider-related works, as well as the 1976 TV Magazine version of Space Iron Kyodain.