Eventually it will totally dry up and won't smell. When my daughter was a toddler, she fell asleep in an upholstered chair and wet herself. I cleaned up the best I could, kept pillows and people off the chair and nature took its' course, the smell is totally gone. I still have the chair. Yes human and cat urine are different. Good luck with your smell.

I really miss having a cat, really, really miss one, but your problem is one of the reasons I don't have one. I had an outdoor cat when I was younger. Last year I rescued one and it was such fun. It jumped out of the carrying case and hit the floor running. It was never still unless he was on his tower in front of the window or on my lap napping. She was such good company, but I just couldn't keep her. She couldn't walk across the floor with clawing it, same with the furniture in spite of the toys I had for her. When she used the litter box, you could smell it all over the house, the garage stunk when I disposed of the waste even in plastic bags. I would go to the store and smell it on me. It was awful. I was in tears when I took her back. The lady knew how upset I was and she said, "don't worry about her, we will find her a good home". I still think of her and get teary.

I hope the urine smell goes away, my carpet man said there is no way to remove the smell from the carpet so I think it would be harder on a piece of furniture.