I have a cat. She is a 15-pound monster with a cranky attitude and fur that she sheds relentlessly, all year long.
She also likes boxes. You can't leave any box on the floor and come back to not find Mei Mei sitting in it. Even little kid shoeboxes; somehow she manages to stuff her fat ass in there.
As this video shows, all cats like boxes. Even really big ones.
Boxes for Big Cats