|Book(s)||Gazu Hyakki Yagyō|
Aka shita is a mysterious spirit which takes the form of a dark cloud with sharp claws and a hairy, bestial face. Its most prominent feature and namesake is its long, bright red tongue and mouth. It appears during the summer months, when rain and water are most valuable to ensure a successful growing season. Only the shape of its hairy, monstrous face and long, bestial claws are known. The rest of its body is perpetually hidden inside of the dark, black clouds in which it lives.
Aka shita are agents of bad luck and evil, and are primarily known as punishers in water disputes. Because plenty of water is essential for keeping rice paddies flooded, Japan’s farmlands are interlaced with an intricate series of interconnected aqueducts and canals meant to deliver water to all of the farmers equally. In times of drought, however, a wicked farmer may open up the sluice gates and drain his neighbor’s water into his own field. Such a serious crime can cost a family its livelihood, and such criminals usually face the violent wrath of their neighbors. Water thieves who never get caught may think they’ve gotten away with their crime, but it is to these farmers that the aka shita comes, draining the water out of their fields and snatching them up with its long red tongue.
Sekien did not attach an explanatory note, so it is not certain whether he intended it as an original creation, but it may be related to the shakuzetsujin (赤舌神, lit. "red-tongued god") which guards the western gate of Jupiter. It may also be related to the shakuzetsunichi (赤舌日), a day of bad luck in Onmyōdō.