Katsumi Nishino, whose name in Japanese is written as 西野かつみ and read as Nishino Katsumi, is a Japanese author and manga writer from Iwate Prefecture. He is a male writer currently living in Morioka, the capital city of Iwate Prefecture. His professional career began when he won an honorable mention at the first MF Bunko J Light Novel Newcomer Award in 2005. He submitted his winning entry under the pen name Nanami Kaoru 2-go, and that story was later reworked and retitled as his debut work, Kanokon. He has humorously noted that despite intending to write a pure love story, he became known by a rather different nickname related to the content of his writing.

Nishino is best known as the original creator of the Kanokon franchise, which includes a series of light novels, a manga adaptation, and an anime television series. The Kanokon light novel series, illustrated by Koin, was published by Media Factory under their MF Bunko J imprint. The first volume was released on October 31, 2005, and the series ran for a total of fifteen volumes, concluding on December 24, 2010. The story follows a naive country boy named Kouta Oyamada who transfers to a high school in the city and becomes the object of affection for two supernatural beings: a four-hundred-year-old fox spirit named Chizuru Minamoto and a two-hundred-year-old wolf spirit named Nozomu Ezomori.

The success of the light novels led to a manga adaptation. The Kanokon manga was written by Katsumi Nishino and illustrated by Rin Yamaki. It was serialized in Media Factory's seinen manga magazine Monthly Comic Alive from August 2006 to August 2010. The series was compiled into nine volumes. The manga has been released in North America by Seven Seas Entertainment, who describe the story as a harem comedy. The original light novel series was also adapted into a twelve-episode anime television series titled Kanokon: The Girl Who Cried Fox. Produced by the studio Xebec, the anime aired in Japan between April and June 2008. A two-part original video animation sequel, Kanokon: Manatsu no Daishanikusai, was later released in October 2009. The franchise was further expanded with a drama CD in 2007 and a visual novel game for the PlayStation 2, titled Kanokon Esuii, which was developed by 5pb. and released in July 2008.

In addition to his work on Kanokon, Nishino is credited as the original story writer for the manga series Juukinzoku Kanojo, which has been translated as Heavy Metal Girlfriend. His body of work is largely defined by the supernatural romance and comedy genres, with a notable emphasis on themes involving human relationships with yokai, or spirits, from Japanese folklore. The Kanokon series, his most significant contribution to the industry, originated as an award-winning light novel and successfully expanded into a multimedia franchise that includes manga, anime, and video games.