What breed is Kitty Kat?

Long haired black and brown tortoise shell. Long tail and about 15 pounds at 15 years old. Female names kitty kat. What breeds are she?

Unless she is registered with a cat association as a specific breed, she is considered a Domestic Longhair. Her color/pattern is tortoiseshell (tortie) and white. She's a beautiful fluffy kitty, but I don't see any features that jump out at me as belonging to any of the registered breeds.