Every cat owner know that cats looove sitting on stuff that they really shouldn't be sitting on. You get up from your chair for half a second? Hi, yes, it's your cat's chair now. You put your laundry on your bed? It'll be full of fur before you even blink. Your laptop? You mean the warm glowy thing that you bought for your cat as a new bed, right? That's definitely what your cat thinks.
There is a line though. There has to be. Because cute as they are, if your cat starts sitting on your turtle, it might be time to get the water spritzer out. Or pause to take a picture, then quickly save your turtle, then laugh. That's also a good option.