I think it's in their DNA. If it's a piece of your clothing they have to lie on it.
Especially if it's freshly laundered.
Whenever I am getting ready to iron assorted laundry, the cat that is closest to the pile always climbs on top of it. I guess they really are cleanliness-loving animals.
This is Matilda, last Sunday.
For me the weekend is pet photoshoot time.