These cats, and their sister (not pictured) are often referred to as “voids.” I’ve come to take issue with this term for my cats. Call your cats what you want, but I think of the black cats in my life as “Singularities.” Void implies nothingness, while a singularity is an object so rich with matter its density is infinite. My black cats are in no way “nothing,” but are, in fact “everything.” People call them voids because they’re invisible sometimes, but singularities are so strong that light can’t escape. Like I said, call your cats what you want, but “singularity” better describes three of mine.