C is for Cat Sidhe

Cat Sidhe is a fairy creature or a transformed witch, with a black body, a white chest, and a variety of reputed powers. From Celtic mythology, the spectral cat was said to roam the Scottish Highlands. People would guard bodies from the cat, who might come to eat the soul before it departed. Some witches were said to be able to transform into a cat nine times, although on the ninth time the witch would be stuck like that forever. There was also a belief that if a Celtic person wanted to know something, they could roast a cat alive, and a Cat Sidhe would come and answer their questions to alleviate the burning cat's suffering.

I like cats, though, so I'm going to stick with the cat-transforming-into-human/witch-Winter-Court-fairy-creature idea. Divination with cats is out for me, I guess.