They’re also known as a "no-face" or "faceless ghost" and they are known to be mischievous rather than malevolent. A favourite game of the Noppera-bo is to work in teams, where one of them scares a victim who then flees and finds another person walking late at night. The victim frantically relates their story to the stranger until they reveal that they too are a Noppera-bo.
Although the Noppera-bo is considered a yokai due to it’s long history in Japanese culture, there are modern reports of sightings, including in Hawaii which has cultural links to Japan.
Nopperabō resembles an ordinary human being in almost all ways, and blends in perfectly with human society. However, the illusion is quickly shattered when met face-to-face, as a nopperabō actually has no face at all. Its head is a blank orb with no eyes, nose, mouth, or features of any kind.
This mysterious yokai is encountered on quiet, empty roads late at night when nobody else is around. Its main activity seems to be scaring humans, which it does remarkably well. They usually appear in the guise of a man or a woman with his or her back turned towards the observer. When approached, the yokai turns around and reveals its terrifying true form, reveling in the terror it inflicts upon its unsuspecting victim. To maximize the effect, they often appear with a face at first, and then wipe their face off dramatically with their hand at the most opportune time.
Nopperabō often work together in groups to scare one individual. As their victim runs away in a panic from the first nopperabō, he runs into another person who asks him what is wrong. When the victim explains what he saw, this person replies, “Oh, you mean like this?” and wipes his face away, just like the first nopperabō. They are even known to impersonate close relatives of their victims, and sometimes a poor man will run all the way home, having run into multiple faceless ghosts only to tell his wife what he saw and have her too reply, “Oh, you mean like this?…”
The nopperabō is a favorite transformation of mischievous animal yokai – kitsune, tanuki, and especially mujina. In fact, so frequently are encounters with this spirit blamed on shape-shifting badgers that the nopperabō is often mistakenly referred to as a mujina.
The Noppera-bō and the Koi Pond tale recounts a lazy fisherman who decided to fish in the imperial koi ponds near the Heian-kyō palace. Despite being warned by his wife about the pond being sacred and near a graveyard, the fisherman went anyway. On his way to the pond, he is warned by another fisherman not to go there, but he again ignores the warning. Once at the spot, he is met by a beautiful young woman who pleads with him not to fish in the pond. He ignores her and, to his horror, she wipes her face off. Rushing home to hide, he is confronted by what seems to be his wife, who chastises him for his wickedness before wiping off her facial features as well.
The most famous The Mujina of the Akasaka Road story recollection of the Noppera-bō comes from Lafcadio Hearn's book Kwaidan: Stories and Studies of Strange Things. The story of a man who travelled along the Akasaka road to Edo, he came across a young woman in a remote location near Kunizaka hill, crying and forlorn. After attempting to console the young woman and offer assistance, she turned to face him, startling him with the blank countenance of a faceless ghost. Frightened, the man proceeded down the road for some time, until he came across a soba vendor. Stopping to relax, the man told the vendor of his tale, only to recoil in horror as the soba vendor stroked his face, becoming a noppera-bō himself.
There are other tales about noppera-bō, from a young woman rescued from bandits by a samurai on horseback whose face disappears; to stories of nobles heading out for a tryst with another, only to discover the courtesan is being impersonated by a noppera-bō.
- The Studio Ghibli film "Pom Poko" features a modern retelling of The Mujina of the Akasaka Road. In one scene, a police officer comes upon a beautiful young woman (who is actually a shapeshifting tanuki) crying on the side of the road. He attempts to console the young woman, but when she turns to him, she has a completely featureless face. The terrified officer runs to a police box to tell his fellow police officer what happened, but the officer, like the soba vendor, strokes his face and becomes a noppera-bo himself. The man then runs to a convenience store (the modern-day equivalent to the soba stand), and tries to tell the people in the store what happened, but everyone in the store then becomes a noppera-bo.
- In the "Axis Powers Hetalia" movie "Paint It, White!", the invading, faceless aliens are occasionally referred to as "Noppera". At the beginning of the movie, Japan explains what a noppera-bo is. In the opening scene, there is a reference to the tales of noppera-bo when a woman flees the Noppera and tries to get help from a police officer, only to find that the officer has just been transformed into a Noppera himself.
- In the game "Adventure Quest Worlds" some monsters in Hachiko Tower are noppera-bo. Such as the Samurai Nopperabo and Ninja Nopperabo, who are fighting in the Yokai Revolution. They kidnapped the real Samurai and Ninjas and are offering them to there leader, a Dai Tengu. They are soon destroyed.
- The anime "Mononoke" is about a medicine seller that searches and kills monsters found in the Japanese folklore. One arc features an Noppera-bo that resembles his appearance a lot. It was never stated who of the main characters in that arc imagined him and so made him seem real.
- The nurses in "Silent Hill 2" has some loose resemblance to the Noppera-bō.
- The popular computer game "Slender" depicts a faceless creature, Slender Man, having resemblance to the Noppera-bō.
- The house artist for the Lovers Knot Rope Company goes by the name of Noppera-bo to hide their true identity.
- Kiyomi Haunterly from "Monster High" is a Noppera-bo.