are monster

Monster

A monster is any fictional creature, usually found in legends or horror fiction, that is somewhat hideous and may produce physical harm or mental fear by either its appearance or its actions...

s found in Japanese folklore

Japanese folklore

The folklore of Japan is heavily influenced by both Shinto and Buddhism, the two primary religions in the country. It often involves humorous or bizarre characters and situations and also includes an assortment of supernatural beings, such as bodhisattva, kami , yōkai , yūrei ,...

. By day, nukekubi appear to be normal human beings. By night, however, their heads detach at the neck smoothly from their bodies and fly about independently in search of human prey. These heads attack by screaming (to increase their victims' fright), then closing in and biting.

While the head is detached, the body of a nukekubi becomes inanimate. In some legends, this serves as one of the creature's few weaknesses; if a nukekubi's head cannot locate and reattach to its body by sunrise, the creature dies. Legends often tell of would-be victims foiling the creatures by destroying or hiding their bodies while the heads are elsewhere.

By day, nukekubi often try to blend into human society. They sometimes live in groups, impersonating normal human families. The only way to tell a nukekubi from a normal human being is a line of red symbols around the base of the neck where the head detaches. Even this small detail is easily concealed beneath clothing or jewelry.

In writing a folktale about nukekubi for his book, Kwaidan

Kwaidan: Stories and Studies of Strange Things

, often shortened to Kwaidan, is a book by Lafcadio Hearn that features several Japanese ghost stories and a brief non-fiction study on insects...

, Lafcadio Hearn

Lafcadio Hearn

Patrick Lafcadio Hearn , known also by the Japanese name , was an international writer, known best for his books about Japan, especially his collections of Japanese legends and ghost stories, such as Kwaidan: Stories and Studies of Strange Things...

 misidentified them as Rokuro-Kubi, an error that also appears in the Fighting Fantasy

Fighting Fantasy

Fighting Fantasy is a series of single-player fantasy roleplay gamebooks created by Steve Jackson and Ian Livingstone. The first volumes in the series were published by Puffin in 1982, with the rights to the franchise eventually being purchased by Wizard Books in 2002...

 book, Sword of the Samurai, and in Stephen Dedman

Stephen Dedman

Stephen Dedman is an Australian author of dark fantasy and science fiction stories and novels.-Biography:...

's novel The Art of Arrow-Cutting. Rokuro-kubi are a similar but distinct class of beings from Japanese folklore; instead of heads that completely sever, the rokuro-kubi have necks that stretch to enormous lengths during night-time. The book Even More Short & Shivery by Robert D. San Souci has a tale called Rokuro-kubi, but the descriptions in the book are Nukekubi, not Rokurokubi.