Cat snake
If you don’t know your animals, don’t put up a Craigslist ad. The reason why he’s “long and nimble” with “dryish fur” is because this isn’t a cat, nor a snake, nor a cat-snake (there is no such thing) but a weasel. You learn something new every day, don’t you?
“Seems to like cat food, but this isn’t a cat” – what a keen observation. This must be, without a doubt, one of the weirdest ads we’ve seen yet. This guy probably found this weasel and tried to get rid of it – he doesn’t even know what it is, so how could he be expected to take care of it?