This is one of our cats, Macchiato. He got his name from the swirl on his side. In Italian, Macchiato means "marked"... I didn't know this when I named him, the swirl just reminded me of the caramel macchiatos I order at Starbucks.
According to Wikipedia on caffè macchiato: The reason this coffee drink got its name was that the baristas needed to show the serving waiters the difference between an espresso and an espresso with a tiny bit of milk in it; the latter was 'marked'.
So his name is even more perfect than I thought!
Except Billy calls him HypnoCat.