The Night Sparrow is a nocturnal attendant yokai widely told of in the mountains of western Japan, marked by revealing itself through its call. In Tosa it is said to look like a small bird, in Kitagawa and Iyo like a moth or butterfly, and its appearance is not fixed. When someone walks alone, it alternates between the rear and the front, chirping close to the ear and throwing off the walker’s rhythm. In Toyama Village a banishing chant is preserved, and people are warned that rashly trying to catch it brings night blindness. In Wakayama, by contrast, it is taken as a sign that wolves are near and as a protective omen against mountain evils. Related tales include the “okuri-suzume” of Nara and Kii and the “tamutori-suzume” of Kochi and Ehime. In Tsunoyama and Johen they are treated as the same, and avoidance methods include gripping one’s sleeve, setting three twigs upright, or reciting specific mantras. Its folkloric traits are its ambiguous visual form, interference through sound, and regional differences in whether it is seen as ill or auspicious.