According to the legend, children walking alone at night may encounter a woman wearing a surgical mask, which is not an unusual sight in Japan as people wear them to protect others from their colds or sickness.
The woman will stop the child and ask, "Am I pretty?" If the child answers no, the child is killed with a pair of scissors which the woman carries. If the child answers yes, the woman pulls away the mask, revealing that her mouth is slit from ear to ear, and asks "How about now?" If the child answers no, he/she will be cut in half. If the child answers yes, then she will slit his/her mouth like hers.