Real name: Hashiguchi Chiyomi (橋口 千代美)

In 1990, she debuted in the June issue of the monthly manga anthology Garo with Nekojiru Udon, which is now considered her definitive work. She committed suicide on May 10, 1998. At the time, the media suggested that it was a reaction to the death on May 2, 1998 of the musician hide—in response to that theory, Nekojiru's husband, Yamano Hajime, said that Nekojiru's musical taste was in a completely different genre to hide, and that her death was unrelated. He stated that "She probably hasn't listened to even one second of hide's music." Without a suicide note, her motivation for suicide remains unclear. Other suggestions include that it was caused by drug use or anxiety over Yamano's womanizing.

With the exception of Tsunami, all Nekojiru's work has main characters drawn as cats. Even in her manga essays, Jirujiru Travel Journal and Jirujiru Diary, she drew herself as a cat. But though the characters appear as animals, the artist chose as her setting not a forest, but rather the human world. Her manga detailing the daily life and adventures of the cats Nyāko and Nyatta are held in high esteem. The major themes of her work are a child-like zaniness, cruelty and nostalgia. And, as we know from Dream Memo, included in the posthumously released compilation Nekojiru Udon 3, many of her bizarre works of fantasy were based on her own dream experiences. Psychedelic mushrooms and LSD also often appear in her works.

Yamano Hajime, using the pen-name Nekojiru-y, took over Nekojiru's world, and continues to produce new works. Currently on his official site, one can read a free chapter of Nekojiru's manga.