The Kappa is a creature from Japanese folklore known for dragging unwary toddlers to their deaths in rivers: a scaly, child-sized creature, looking something like a frog, but with a sharp, pointed beak and an oval-shaped saucer on top of its head, which hardens with age. Akutagawa’s Kappa is narrated by Patient No. 23, a madman in a lunatic asylum: he recounts how, while out hiking in Kamikochi, he spots a Kappa.…