In Japanese folklore, the yōkai known for stretching its neck to extraordinary lengths at night is the rokurokubi.
Rokurokubi are supernatural beings in Japanese folklore whose heads can separate from or extend away from their bodies. In many stories, they appear human during the day and reveal their unusual ability after dark. Some accounts describe the neck as lengthening dramatically, while others portray the head as flying independently.
Rokurokubi are often confused with nukekubi, a related yōkai whose head detaches completely and flies away. The distinction is not perfectly consistent across all retellings, but the stretched neck is the characteristic feature most strongly associated with rokurokubi.
The word is commonly written with characters meaning “pulley neck,” reflecting the image of a neck extending like a rope or mechanical line. These tales belong to the broader tradition of Japanese yōkai stories, which often explain strange nighttime encounters through supernatural transformation.