The creature below is Puzzle, a cat of indeterminate age and size. It is a calico cat and like virtually all such cats is female — coat color in cats is X-linked, and since males have only one X chromosome and females have two, males (except for the very rare XXY ones) cannot exhibit the mosaic patterns of fur coloration.
I haven’t seen anything about calico cats tending to be overweight, and there’s no reason I would since “calico” describes a color, not a breed. But almost all of them I’ve encountered have been felines of size, and Puzzle’s no exceptions. She sounds like she has sleep apnea and when awake tends to make some unusual noises.