Hisashi Eguchi was born on March 29, 1956 in Minamata, Kumamoto, Japan. He is a Japanese manga artist and illustrator recognized as one of Japan's most prominent creators of female character illustrations. Eguchi made his professional manga debut in 1977 with the series Susume!! Pirates, published in the anthology Weekly Shōnen Jump. His most notable manga work is Stop!! Hibari-kun!, a romantic comedy serialized from 1981 to 1983, which was adapted into an anime television series in 1983. He is also known for the gag series Charamono. In 1992, he received the 38th Bungeishunjū Manga Award.

Several anime works are credited directly to Eguchi as an original creator. The original video animation Eguchi Hisashi no Nantoka Naru Desho!, released in 1990, is an adaptation of his short story manga collection. This OVA is notable for its mixed format, combining animated segments, live action, and puppetry. Eguchi described one of his favorite scenes from this work as being very dark, which presented a challenge for the animators. The OVA Eguchi Hisashi no Kotobuki Goro Show was released in 1991. Based on his gag manga, it was originally released as a feature part of Studio Pierrot's video magazine show Anime V Comic Rentaman. The show consists of four short, vulgar comedic pieces, with episodes parodying genres such as giant monster films and boxing dramas. The manga series Eiji, written and illustrated by Eguchi, was serialized in Shueisha's Fresh Jump magazine from 1984 to 1985. It was adapted into a 45-minute original video animation released on August 25, 1990, produced by I.G Tatsunoko and directed by Mizuho Nishikubo.

Beyond his own manga, Eguchi has worked extensively in the animation field as a character designer. He provided character designs for the films Roujin Z, Mujin Wakusei Survive, and Otaku no Seiza. The characters in the film Perfect Blue were also based on his designs. He used his wife, idol Mari Mizutani whom he married in 1990, as a model for the character Haruko in Roujin Z. His artistic identity is characterized by a simple style that favors organized, clean lines. He has stated that American pop artists such as Roy Lichtenstein and Andy Warhol have influenced his work, as have European cartoonists Moebius and Hergé. In 1994, Eguchi founded Comic Cue, an annual alternative manga magazine, describing his desire to create a gathering of his favorite artists akin to an all-star game or a team of superheroes.