What is it about cats and wet concrete!
I'm in the process of building a gated wall between our new 'tower' and the house. One half is already done, and I'd just laid the concrete foundations for the other half when along comes Freddie. In this case they will be covered over, so he needn't have bothered.
When I was small my father designed, and had built, a rather nice, traditional, Surrey/Sussex style, tile hung house, with a large concreted terrace overlooking the rear garden. Cat paw prints were all over the terrace from day one, and no doubt are still there. I think we wouldn't have had it any other way. It's kinda traditional!
So, Freddie, your signature will probably be buried by tomorrow lunchtime; and you'll have to look elsewhere for your feline immortality.