According to the food-chain, rats and cats are mortal enemies. However, this concept is now deemed to be false. Now-a-days it is only taken as stereotyped perspective as we have seen a lot of examples where animals from completely different species communicate and have a close relationship; like cats and dogs.
Even though street cats and rats may be enemies even now, it doesn’t seem to be the case for the domesticated cats and rats. And this video below is the perfect example for it!
In the following video, we can see a fearless rat approaching a cat.