I tried to name my cat Lou (short for Lucifer) but eventually he got renamed Mao because he is loud and vocal and apparently we name animals by Pokemon rules in my house.
I have a cow cat with one big black spot on the top of his head and on big one on his back. He’s a very big boy who looks rather imposing but he’s really sweet. We call him Kenny or Kenny-chan but his real name is Kenpachi (from Bleach). Coincidentally he lost an eye to cancer over a year ago so he looks even more like his namesake now.
I also had/have a cat named L.T! It was short for “little tip” because he had just a tiny tip of white fur on his tail, otherwise a standard issue brown cat. The tip darkened away to nothing as he got older and he hops down stairs both front feet at once, so now his full name is Lieutenant Jack Rabbit.
This was discounting the truly lazy ones where I just add -boy, -girl, and -cat to the end which adds an infinite supply of stupid names. We took Gyaos to a different vet than our normal one once (for a paw he cut on some glass he shattered) and they acted like Mouse was the weirdest nickname in the world. We didn't return to them ever again.