The problem is one has a sensitive system and has loose stools. It wouldn't be so bad, but he doesn't always get himself very clean. (I'm trying to be as tactful as possible.) I like feeding a premium cat food and have tried a couple, but it takes about 6 months to phase it in. We're trying a sensitive stomach one right now; they like the size, but I haven't seen any improvement.
I follow around one of my cats with "diaper wipes" trying to clean him, so any suggestions are very much appreciated.
I feed mine Royal Canin. Right now they are still on kitten food but there are several "special" diets available. They even have breed specific diets and Persian is one of them which is why I started them on it. But they have diets for digestive problems and oral health problems as well under the Special category. You can get it at any major pet supply store too. If you check out their website you can see the size and shapes of the kibbles for each type of food by rolling your mouse over the picture of the bag of food. My youngest kitten is so tiny that I am using the "babycat" formula right now because the kibble is nice and small for her and I wanted to fatten her up a bit. But my 4 month old prefers it's taste as well. I switched to it slowly from Kitten Chow and I haven't had any issues with messy bottoms. Persians have sensitive tummies as well and I did have some cleanup issues when I made the mistake of giving treats or when they got into the dog's bowl. I feel your pain. It is really bad when you pick them up for a cuddle before doing a butt check. If your cat has long hair, you might try trimming the fur back there to help minimize the problem.