I think granite would be so slick your pup may end up injuring herself getting up and down from it, plus it won't be good for her joints to sit on such a cold surface.

Since she likes the area, I'd make it comfortable for her by putting in a cushion with a removable, washable cover. Check out the sunbrella fabrics for a more durable cover....especially if you have a large dog.

I agree with Ann.

Yes, I'd just do a cushion with a washable blanket on top.

Your post made me smile because your project idea proves once again that we who include animals in our families do make all kinds of design accommodations in our homes for them! Love it! The cushion & pillow option is good & concerns for dog slipping or not being comfortable on hard & cold surface like granite are ones I agree with. I wonder about a pillow slipping too with dog jumping up & down. We don’t know size of dog or if it matters & we don’t know size of window shelf / ledge but it looks quite large. I wondered if you could find a runner rug with either a rubber backing or if a non slip backing as would be used on floor could be placed under a runner that didn't have a non slip back. if you happen to have carpet remnants from your carpet on floor, you could cut to size & have edges bound & put on top of non slip. Seems like the rug to fit space would be least expensive & easiest to remove if needed.

She has a nice big sitting window there, what a lucky dog! Mine likes to sit in front of the front door (glass) and watch the property -- it's like the doggie version of television.

Agree with above re: cushion. You could do a snazzy full length cushion then a throw blanket in her sitting area. The rug idea is a good one, too -- easy to find inexpensive remnants.

She absolutely loves sitting on the marble of my fireplace, but it’s missing this window view. My thought is even with a blanket or carpet the drywall under is still going to get dirty. If I did put granite down and carpet on top for slippage would that work? My neighbor put tile on his for his dog. I just don’t like the look of the grout.

How about a solid surface with a honed or leathered finish to reduce slipperiness? You mif find a remnant at a local stone yard & i think the surface can be refinished if it has a highly polished slick surface. Stone yards do have all sizes of remnants in lots of materials. I know bc I just had new counters installed & since I had to buy 2 jumbo slabs I had enough left over to install a 22” x 55” guest bath counter & a 15” x 38” freestanding cabinet top & still more left! With solid surface mind the edge you have fabricated- I think an eased edge better than sharp one.