This is a picture of the cat condo my dad, Harry, made out of cardboard. He loved building things and was very adept at working with cardboard since he worked at St. Regis for years as a box designer. Softie, another all black cat, is inside on the second floor. Sorry you can't see it too well in this picture.
If you have cats, you know they love boxes, right? I had fun making one for my two cats, Spunky Doodle and Manny Boy using boxes from Christmas in 2012. I even put a musical Christmas card down in the bottom left corner by the "welcome" sign that played when the cats popped the card open. This stayed in our upstairs hallway for some time (I think my husband thought I was nuts, but put up with it.) Can I help it if I take after my dad? You might enjoy reading Spunky Doodle's post: "We Got Boxes" that also includes my video demonstrating how to make a cat condo with Spunky Doodle in action. You really should take a look!