All sorts of creatures are found linked with magic. Sometimes this is because they are, by nature, magical beasts— such as dragons and unicorns and griffins. Sometimes they are enchanted humans— frogs and toads, in the main. Sometimes they are ingredients—usually of the multi-legged, creepy-crawly variety. The entire animal is not always required— i.e., hair, claws or whiskers will often do just fine.
The animal that crops up time and time again in the worlds of Chrestomanci, and particularly in connection with witches, is the cat. One of the prime reasons cats are such magical creatures is because they have nine lives. As Chrestomanci HAS to be a nine-lifed enchanter, it stands to reason that any creature with the luck, gifts and abilities of nine lives is going to be far more magical than a creature with just one! Which means that all cats are magical, even though their owners are probably not.
Knowing this makes cats extremely confident and self-sufficient, and they put their magic to use all the time. How else could they appear from nowhere when a fridge door is opened? Or make a human open door or window for them when they have a perfectly good cat flap of their own? Or seek out and snuggle up to the one person in the room who hates cats? Most of the time, cats don’t waste their energy displaying their superiority to non-magical humans. Occasionally they will, however, try to communicate with them—perhaps by staring at their subject for a very long time, or by sitting/standing/sleeping on whatever book/newspaper/homework that person might be occupied with, or by massaging that person’s leg/stomach/shoulder with very spiky claws while purring loudly.
Cats tend to behave in the same way regardless of whether they live in a world with a lot of magic or a world with none. But in worlds that use magic every day, cats can be extremely useful—if they can be persuaded to help you at all. Of course, it’s a great advantage if you can understand cats; not everyone can—not even every magic user can. (In fact, we learn that not even Chrestomanci can understand cats in The Magicians of Caprona—although he knows how to communicate in the proper manner.) It’s therefore not surprising that Tonino Montana gains much respect from his friends and family when Benvenuto—boss cat of the Casa Montana—takes Tonino under his wing. Benvenuto knew that all Tonino needed was a bit of help in learning how to use his special kind of magic—and the fact that Tonino also knows exactly the right way to scratch a cat behind the ears is just a big feline bonus!
No doubt similar reasons brought Angelica Petrocchi and Vittoria together in the rival Casa Petrocchi household. In some worlds, cats are so magical that they are sacred. The Temple of Asheth in Series 10, for example, is positively swarming with magical cats. The Goddess usually adopts a favorite as a companion and to aid her in her reading of portents. In The Lives of Christopher Chant, the Goddess’s cats were Bethi, succeeded by Proudfoot. Asheth Temple cats all have exceptionally strong personalities—the strongest being that of Throgmorten. No cats suffer fools gladly, but Throgmorten is probably the least tolerant of all and has no hesitation about venting his feelings with his razor sharp claws, lethal fangs and lightning quick reflexes. Throgmorten is a very handy ally in a fight against a deadly foe, but is not averse to ambushing innocent bystanders if he doesn’t like them!Some cats are not what they appear to be. Fiddle, in Charmed Life, was actually once a violin (hence the name). But never make the mistake of thinking that an enchanted cat is any less important or magical than a cat that grew up from a kitten—he may well have a vital role to play as all magic happens for a reason.
The best advice for dealing with cats is: Always greet them politely. Don’t make an unnecessary fuss over them. Be on the alert for signs they want to communicate with you. Never, EVER laugh at them! If you’re lucky, you might just find that your cat will decide that you are a magical person worthy of attention. Or then again, maybe they’d just like some fish…
— Diana Wynne Jones, “The Importance of Cats”