I don’t recall any nicknames that stuck to me. I am a bit stuffy about such familiarity. My cats, however, don’t get any respect.
Andy has at least two nicknames. “Pretty Boy” and “Pretty Tail”, spoken in an excited tone. Spoken while petting him, these words seem to suit Andy’s needs.
Dougy gets the stick with his nickname, but he’s so mellow he doesn’t care. Yep, his nickname is “Chubs” because he is a bit porky. Not bad, but to a point I make sure to get his veterinarian’s opinion about it each time the boys go in for checkups and booster shots.
Endearments are simple. Both are “Sweety”, because they are. Same for “Good Boy”, which mostly is true!
The boys’ nicknames came out of the confusion I endured when they were kittens and looked identical. Revisiting the videos and photos from that time, I can see the distinctive Andy and Dougy characteristics that weren’t so obvious then. The endearments come out of affection, of course, for a couple of pretty good cats.