I have a dozen or so of these, in all different colors and styles. I’ve got a couple of dogs as well, and I’ve even seen a bunny! Most places try to pass them off as “toothbrush holders” or “planters,” but actually they were air fresheners. (Though I do use one to hold my toothbrush!)
The tail acted as a wick for whatever kind of gooey air freshener liquid was in the body of the kitty, and pulled the scent up and into the air. When you find one with a tail, it’s a fairly rare occurrence. They are pretty common, otherwise.. I would guess almost every collector has a few or has seen them around. Every one is different. I have them in pink, blue, green, red, gray, etc. The amount of color vs. white on each also varies. Yellow seems to be the color I see most. Too bad they don’t make them anymore, modern air fresheners are pretty boring in comparison!
If you see one with a much larger hole in the bum, those were probably planters, usually with a wacky cactus sticking out the back to form the “tail.”