Kay Eaton was a science fiction writer who wrote under the pseudonym of "K.C. Hunter" in the 1950s in order to conceal the truth, from the more conservative elements of that era, that she was in fact a woman. She is best known for her work on the New York based Incredible Tales magazine.
Kay often worked in conjunction with her husband Julius Eaton and the two had something of a reputation among the magazine staff for turning out slightly sentimental stories, particularly by Herbert Rossoff. Because she was a woman, and consequently discriminated against, Kay felt some solidarity with Benny Russell, the staff's only African-American writer.
When Benny submitted his story about a space station, Kay was very impressed with the character of Major Kira Nerys, describing her as a "tough cookie" and saying science fiction needed more strong women. (DS9: "Far Beyond the Stars")
Kay Eaton was played by Nana Visitor, who usually portrayed Kira Nerys. Ronald D. Moore once remarked, "K.C. is not a literal translation of Major Kira. But it [the episode 'Far Beyond the Stars'] was written in such a way where you could see where Benny Russell would have used her as an inspiration." (Cinefantastique, Vol. 30, No. 9/10, p. 125) Visitor described her experience of portraying the character; "Personally, I felt like [wise-cracking star] Eve Arden, and it didn't feel good!" she laughed. (Star Trek: Deep Space Nine Companion, p. 535) Visitor also divulged, "I fashioned my look on a self-portrait my mother had done of herself when she was my age at that time period – and I looked eerily identical. In one of the shots, I took the pose she was in – hand to chin – and it was a little secret homage to my mother."   At the time "Far Behind the Stars" was filmed, Visitor was married to Alexander Siddig, who played Kay's husband Julius.
Kay Eaton was inspired by Catherine Moore, a prominent female science fiction writer of the 1950s who often collaborated with her husband, Henry Kuttner, and hid her gender behind the byline C.L. Moore. (Star Trek Monthly issue 40) For a variety of reasons, there are many female authors in the Star Trek genre for whom this naming convention continues to be used. These include J.A. Lawrence, J.M. Dillard, A.C. Crispin, M.S. Murdock, D.C. Fontana, V.E. Mitchell, L.A. Graf, T.L. Mancour, E.L. Flood, W.R. Thompson, S.D. Perry, and S.N. Lewitt.
Kay's last name comes from the script.
Though it is not stated, the authors of the Star Trek Encyclopedia (4th ed., vol. 1, p. 228) might have thought, as they did with her husband, that Kay Eaton "might have existed in some alternate reality, or perhaps only in certain reaches of Ben Sisko's mind."
Kay Eaton appears in the novel Star Trek: Typhon Pact: Raise the Dawn as a vision experienced by Kira, where she helps Cassie rescue Benny Russell after his transfer to prison, the vision inspiring Kira to save Sisko by seemingly sacrificing herself.