The filing fee is only $45, so applying for a copyright should be done as a matter of course whenever possible. With respect to inventions, you should be thinking about getting a patent of some kind. The options are getting a utility patent, getting a design patent or both.
Height and weight and size for a calico cat? The colour of the cat's coat does not depict its overall shape and weight. The average weight of a cat is usually about 8 - 16 pounds. Cats average about 23 - 25cm in height and 46cm in body length, not including the tail.
There is also a calico cat breed called a Dilute Calico. Dilute Calicos are not necessarily rare, but they are for sure more rare than the normal calico. They are recognized by their grey, silver, and gold colors instead if the traditional white, black, brown or red patched coat of a calico.