Surgical masks are most frequently worn by health professionals, but in many Asian countries they’re worn simply as a way of protecting oneself from the smog, a common problem in that part of the world. Asians also wear surgical masks when sick in order to not infect anybody else. Interestingly, such a simple everyday thing is involved in one of the most uncanny of popular legends in Japan.

Kuchisake Onna, or “slit-mouthed woman” in Japanese, was originally a extremely gorgeous woman whose jealous husband cut her mouth from ear to ear, taunting, “Who will think you are beautiful now!” Ever since then, on foggy nights, she can be seen roaming around in a surgical mask. When she encounters somebody, typically youth, she will shyly inquire whether the individual thinks she is beautiful.

If the answer is yes, Onna will take off her surgical mask and ask, “How about now?” Different versions of the legend give various outcomes if the answer remains affirmative, all bad: she will either cut the individual from ear to ear to resemble herself or kill the person – or both – or, inexplicably, give a large blood-soaked ruby and walk away.

Different versions of this tale offer for the same general set of choices even if the original answer had been negative – mutilation or murder. Basically, meeting Kuchisake Onna is bad luck. However, much more modern versions nowadays advise that responding “You’re average” or “So-so” or even asking her what she thinks of one’s own beauty will turn the tables on her and confuse her, providing an opportunity to escape.

And, in one of those only-in-Japan kind of things, there is even the tactic of simply informing her that you must be on your way, so as to embarrass her for forgetting her manners and making her excuse herself from your presence!