Kyōko Okazaki was born on December 13, 1963, in the Setagaya ward of Tokyo, Japan. She began her professional career as a manga artist in 1983 while still a student at Atomi University, making her debut with a short story published in Manga Burikko, a magazine known for its adult male demographic. After graduating in 1985, she published her first manga series, Virgin. Her reputation became firmly established with the 1989 work Pink, which tells the story of a young office worker who works as a call girl at night to support her pet crocodile.

Okazaki is recognized for a number of significant original works. Pink was followed by the series Tokyo Girls Bravo, which was published in the mainstream fashion magazine CUTIE. In 1992, she released Happy House, about a thirteen-year-old girl seeking emancipation from her preoccupied parents. From 1993 to 1994, she serialized River's Edge, a story depicting the conflicts and problems of high school students living in a Tokyo suburb. Her most famous work, Helter Skelter, was serialized from 1995 to 1996 in Shodensha's monthly magazine Feel Young and later published as a single volume in 2003. The story follows a fashion model whose body has been entirely transformed by cosmetic surgery, illustrating the obsession with beauty and the resulting psychological derailment. Her career as an active creator concluded abruptly after a severe traffic accident in 1996, and she has not published new work since that time.

The adaptation history of her work includes the 2012 live-action film Helter Skelter, directed by Mika Ninagawa. In the same year, Okazaki made her first public comments following the accident in conjunction with the film's release. Her past works continued to be reprinted and were also adapted into live-action movies. In 2013, the English edition of Helter Skelter was published by Vertical, Inc. under the title Helter Skelter: Fashion Unfriendly.

Okazaki's artistic identity is defined by her focus on contemporary urban life in Tokyo, capturing the zeitgeist of Japanese society during the economic transition from the bubble economy of the 1980s to the Lost Decade of the 1990s. Her work is noted for breaking the norms of shōjo manga from the 1970s through explicit depictions of female sexuality and themes such as sex work, homosexuality, incest, and the effects of capitalism. She is also considered an early forebear of the gyaru manga style. Her protagonists often embody a sense of loneliness and emptiness, navigating a world of material consumption only to be overshadowed by doubt and regret. Her storytelling frequently incorporates intertextuality, with references to popular culture, including films, novels, pop music, and other manga.

Her significance to the manga industry is underscored by the critical recognition and lasting influence of her work. For Helter Skelter, she received the Excellence Prize in the manga division of the Japan Media Arts Festival in 2003 and the Tezuka Osamu Cultural Prize in 2004. More than two decades after her career was halted, her work continues to be discussed in academic literature for its thematic depth and remains in print, attracting new generations of readers. A large-scale exhibition of her work, titled Okazaki Kyoko Exhibition: Girls Life on the Battlefield, was held at the Setagaya Literary Museum in Tokyo and later traveled to other cities in 2015 and 2016, featuring over 300 manuscripts and original drawings.