When you have a litterbox next to the couch with a little kitty-stairway from the couch down to it for your oldest cat so she doesn't have to go far to go, and also a litterbox ON the couch for when she doesn't feel up to going down the steps to the box on the floor, and plastic covering and towels on the couch for when she overshoots the edge of that box... all this because she likes to rest on the couch but sometimes leaks.

I will get a photograph or two or three when I have a chance. She's not on the couch right now but down in her little hideaway in the cabinet under the TV.