Hi again, and thank you for the additional information!
Usually, when a cat starts eliminating inappropriately, it's either due to a medical reason (urinary infection, crystals [tiny, grit-like particles which occur in urine that is not pH balanced]), or it has a behavioral cause.
First, you have to rule out the medical reason, so the cat who is urinating on the beanbag chair needs to see the vet as soon as possible for a definitive diagnosis and treatment, if necessary.
If it's the male cat that started urinating outside the litterbox, keep in mind that urinary infection or possible blockage is much more dangerous in a male, if left untreated.
If a cat experiences pain upon urination or defecation, s/he will come to associate the PLACE of eliminating--the litterbox itself--with that pain, and then choose to eliminate ANYWHERE else. Cats in this situation usually choose 'soft' materials to go on, thinking this will avoid the pain.
In order to prevent your cat from returning to the places s/he's already soiled (if s/he smells it, s/he'll keep thinking they are appropriate toileting places), you can use an enzymatic cleaner to completely remove all traces of stain and odor. Nature's Miracle is a good product for this purpose and can be found in Petsmart/Petco, most pet supply stores, and online. For more info and to view all related products, please see:
http://www.petcarecentral.com/nm-155.html
If the beanbag chair is covered in material or vinyl, Nature's Miracle should help. However, you might have to end up throwing it out, due to the nature of the object.
Cats can also sometimes start eliminating inappropriately if there has been any kind of change in their lives or environment, as this causes stress and anxiety. If the reason for eliminating outside the litterbox is NOT found to be medical, it would be considered behavioral.
Cats are creatures of habit and do not take kindly to change. If you have had any new people added to your household, or if a 'usual' person has left, if you got new furniture, carpet, appliances, another animal, etc., or if your usual daily hours at home and/or away from home have changed, or you've gone on vacation recently, any of these situations could cause your kitties stress.
Feliway is a product made from a synthetic feline pheromone which can help to calm stressed cats and curb urine marking or inappropriate elimination. It comes in both a spray and plug in diffuser form. The diffuser plugs in to an electrical outlet like an air freshener, but has no scent to humans.
For more information, please see:
http://www.catfaeries.com/feliway.html
www.felineway.com
Major pet supply stores like Petco/Petsmart carry Feliway, you can also order it online, and some vet offices carry it.
There's another product which I think may help you get your kitty back to the litterbox--it's a clumping kitty litter called 'Cat Attract'--it contains herbal attractants which encourage use of the litterbox. It too, may be found in major pet supply stores.
The rule of thumb is usually one box per cat, plus one. If you have a multi-story house, a box on each level is also appropriate and usually prevents accidents. Keep all boxes immaculately clean at all times. I would suggest that you uncover the covered box, as this really keeps in odors, and might be unpleasant for your cats. If both cats seem to like the covered one better, then they may be used to the 'cover' and prefer more privacy. Perhaps try covering the other box as well. Try to place both boxes in different areas of the house. Also, try adding the third box.
Keep in mind that first you should get your one cat to the vet to determine if the cause of eliminating outside the litterbox has a medical basis.
I hope all goes well, and please let me know what the vet says.
Cher
If my answer is helpful please click ACCEPT. Click reply for more info. Please talk to me before considering leaving neg. feedback; my only goal is to provide helpful answers. Thanks!