Satou Arifumi (1939-1999) was a Japanese occult & horror story writer. He was known for writing a number of picture books about monsters, youkai and demons aimed towards children in the 1970s. He was notorious for having a large number of lies and falsities he made up himself in his explanations. It was not uncommon in his books for him to introduce originally harmless creatures with explanations such as "they eat the insides of a man's stomach" or "a man who talked to it was infected by mold."
Researchers and dilettantes of youkai believe that the ridiculous explanations added later, such as the word play, jokes, parodies, or sarcasm for entertainment purposes actually played an important role in the birth of "traditional" Japanese youkai. The four works of Toriyama Sekien are a prime example of this. In fact, many of the youkai whose names, abilities, origins, and so forth were established in the 1960s and 70s are essentially "youkai born in the Showa era." Of those, Satou's horror stories are directly attributed to a number of them.
However, Satou's method was anything but ordinary. In a certain book he made "Ghour [not ghoul], the cannibal demon of Portugal" from Goya's ”Saturn Devouring His Son” and the Swedish "Throwing-down demon" who threw frozen dead bodies into peoples homes from Rops' ”Satan Sowing Seeds,” using the original pictures just as they are.
Kagenashi-dog (影なしドッグ, literally "The Shadowless Dog") is one of the monsters he created. The original image was a wood engraving print known as "Mimick, or Getulian-Dog" from Edward Topsell's "The History of Four-footed Beasts".
He explained the beast as "a dog cursed with having fur entirely made of silver in the day time, which turned all black at night. It is said that no light will give the dog a shadow, and if you are haunted by him 13 unlucky disasters will fall upon you before your death."
However, the funniest part of the Kagenashi-dog isn't the explanation, but the fact that there are clearly shadows at the dogs feet in the picture.
