In Cruel and Unusual Magic, Julian and Hex meet the Fudo Demigod Tora and her Bakkei Neko, Maru. Maru is so large, Tora can ride him. Maru may be monstrously large but he is not an evil demon cat. Instead he helps Tora protect humans from Japanese Yokai - supernatural creatures -- and Oni -- Japanese demons. Hex, Julian's werecat, develops a crush on the manly Tom.
Cats were often associated with the dead In ancient Japan — some cat spirits of legend steal corpses. Bakkei Neko are not born but made. A house cat can become a Bake Neko (also callednekomata),though the timeline for this is anywhere from ten to a hundred years depending on the legend. Their tail mysteriously splits in two once their paranormal powers manifest and some may kill their master and shapeshift into their place. (Thumbs at last! Come to me, my can opener, my darling...)
Anyone who has seen Japanese street cats will notice that bobtails prevail. It’s a recessive gene common in Japanese cats. To become a Bake Neko, tails must be long. Bobtails cannot turn into Bake Neko,since they have no long tail to split in two as part of the transformation. Perhaps one reason for the bobtails enduring popularity.
Sanrio's Hello Kitty is a bobtail, did you know? No transformation into a demon for her!!