Cats are the wicked version of the multi-tailed whip.
It's classic archetypes can be admired in old pirate flicks. The mutineer or sailor was tied onto the mast and flogged with a cat o' nine tails. As a rule, whips made from braided leather or rope were used. To increase the intensity, knots were attached or even hard object were braided into the ends.
Our cats are constructed a little less robust, since they shouldn't really cause injuries. They nevertheless belong to the the heavier group of SM toys.