Well, I'll tell ya anyway. According to Lesbian Life: "Kiki is a term that was used in the lesbian bar culture of the 1950s and 1960s to describe someone who was neither butch nor femme. At that time, the bar culture was very much into roles and most women were pressured to choose either butch or femme."
So I'm guessing that, used as a verb, it describes behavior that does not peg which part of the gay subculture you're in
Well, at least it's something that doesn't require hand sanitizing afterwards.