@Pokemoll; When we got the first two cats (Charlie and George), both of whom have nothing in common with dogs, one of my sister's friends was going to Paris for Christmas and she left us to take care of her guinea pig. We had to keep it in a separate room and the cats couldn't go in unsupervised. One time when they came in supervised, they circled the cage licking their lips. The poor thing probably nearly had a heart attack.
Weirdly, though, we had our own pet fish when we got those cats initially, and the cats had no interest in trying to eat the fish. No, they just wanted to drink the fish tank water which was full of fish poop and decaying fish food. Fuckin' weirdos.
Well, except he has a bit of a hairball problem.