Well, the first thing I thought was that, yes, the cats are all way bigger than they should be compared to Deva. But my second thought was of Deva fangasming over finally having pets big enough for her to roughhouse with.

Deva: "And then when they were all tired out, I would totally try to fit as many of them inside me as I could too."

And how big are the felines supposed to be then?=v=

Well, Deva is supposed to be at least 12 ft. tall. So she's roughly twice the size of the average human.
http://beforeitsnews.com/mediadrop/.....20dbbeffd9.jpg

Google "tiger hug" or "lion hug", and most of the images that show the cat on its hind legs have it at near or equal height to the human.
http://pixdaus.com/files/items/pics.....5bc5_large.jpg

So an adult big cat and Deva would have a size difference closer to that of a human and a medium-sized dog.
http://www.bforbel.com/wp-content/u.....1407748134.jpg

But like I said, it's still awesome and adorable (awesdorable?). And I've already conceived of multiple ways this could feasibly fit into the canon too.

Deva: "I badgered him into it. Sometimes it gets lonely up here with the basketball hoops."

Heh, okay.^v^