Toshio Maeda was born on September 17, 1953, in Osaka, Japan, and emerged as a highly influential manga artist known for his work in the erotic genre during the 1980s and 1990s. His early life was marked by voracious reading; he has stated that he consumed over 10,000 books before the age of 20, and he was particularly influenced by American comics such as Mighty Mouse, Spider-Man, and Batman, as well as the dark atmosphere of Japanese rental manga. At the age of 16, he moved to Tokyo to work as an assistant to the professional cartoonist Kenji Nanba, an experience that helped launch his career as a manga creator.

Maeda is the original creator behind a number of notable manga series that were later adapted into anime, particularly original video animations (OVAs). His best-known work, Urotsukidōji (Legend of the Overfiend), began as a manga series in 1986. This series gained significant notoriety and was adapted into several anime productions, including Chōjin Densetsu Urotsukidōji: Hōrō-hen Jain Kanbanzen, Chōjin Densetsu Urotsukidōji: Kanketsu-hen, and Chōjin Densetsu Urotsukidōji: Kyōō-hen Gekijō V2 Kyōya Majū-den. Another of his credited original works is the Adventure Kid manga, published from 1988 to 1989, which was later adapted into a three-episode OVA series beginning in 1992. His 1989 manga Yōjū Kyōshitsu Gakuen served as the basis for the anime Demon Beast Invasion, which was released as an OVA starting in 1990 and followed by a sequel series, Demon Beast Resurrection, in 1995. Many of his other works, including La Blue Girl and Demon Warrior Koji, have also been adapted into anime.

Maeda's artistic identity is closely tied to his role in the proliferation of the tentacle rape genre. He has explained that this motif originated as a practical solution to Japan's censorship laws at the time, which restricted the depiction of genitalia. By using a creature's tentacles, he could depict sexual situations that would bypass censors, as a tentacle was not legally considered a penis. He has also noted that tentacles allowed for greater artistic creativity, as they were not constrained by gravity and enabled a wider variety of poses for his characters. His work is often characterized as a blend of erotic horror, science fiction, and fantasy, and his influence has been described as foundational to the erotic-grotesque genre in anime. While best known for his adult-oriented material, Maeda has worked across a variety of genres, including educational manga, political manga, and works for younger readers.

Maeda's significance within the industry is considerable. He has been referred to as the pioneer of hentai and the most influential erotic manga artist in Japan, with his work Urotsukidōji often cited as the foundation of the genre. In October 2001, he was a Guest of Honor at the Big Apple Anime Fest in New York City, where he served as the keynote speaker. A motorbike accident in 2001 limited the use of his drawing hand, but he has continued to work using a computer to create characters and write scripts. In 2010, he opened his official website, the Tentacle Club, where fans could view his work. His influence and legacy as a creator are widely recognized, with his works being credited as some of the most influential in the English-language anime and manga market.