Wikipedia
is a figure appearing in Japanese urban legends. She is a woman who was mutilated by her husband, and returns as a malicious spirit. When rumors of alleged sightings began spreading in 1979 around the Nagasaki Prefecture, it spread throughout Japan and caused panic in many towns. There are even reports of schools allowing children to go home only in groups escorted by teachers for safety, and of police increasing their patrols. Recent sightings include many reports in South Korea in the year 2004 about a woman wearing a red mask who was frequently seen chasing children, and in October 2007, a coroner found some old records from the late 1970s about a woman who was chasing little children. She was then hit by a car, and died shortly after. Her mouth was ripped from ear to ear. Although some stories describe her as a former patient of a mental asylum, the more common story describes that her husband found out that she was cheating and used a sword to cut her mouth from ear to ear and shouted "Who will think you are beautiful now?"