Kittycat is based on a cat I inherited with the first house I bought. The owner was moving across town and was worried, saying, "Kitty will keep coming back here if I take it with me." So I kept Kitty and added a cat door to the kitchen. Kitty was a longhair white old male and went roaming, was sometimes gone for days, then would wander in with a torn ear from its latest cat fight and demand food. Very funny critter, very independent, didn't even like its ears scratched.
You can imagine the fun I had the day Kitty wandered out into the adjacent orchard where a worker was spraying the trees with an insecticide. Kitty ran home dripping wet and started to lick himself clean. I had the choice of dead cat or bloody me. Yeah, of course, I grabbed Kitty and held him down in the laundry sink and scrubbed him clean and got thoroughly scratched for my effort.
We had a one way love affair that matches Kittycat's relationship with Claire.
As to gender, Kitty was male, but Kittycat is fiction and so can be whatever the reader prefers.