I recently learned this word while reading Chibi Maruko-chan: 地獄耳 (jigokumimi) – The ability to remember everything one hears, or the ability to instantly hear secrets and rumours (having a sharp ear). You’ll notice that 地獄耳 (jigokumimi) is composed of the word for hell (地獄), and ear (耳) of course. But why hell? This is what got me intrigued. And apparently, there are a few theories to the origin of this word.
The first theory: it is believed that the human world is closely watched by the devil in hell, to see if we say or do anything bad. As soon as a human utters anything bad, the devil will be sure to hear this, and remember it for when the time comes. こわいい〜 (((( ;°Д°)))) Indeed the devil would need a sharp ear to hear all the way from hell.
The second theory: Once you fall into hell, you’re sure to never come back out again. Therefore, once you hear something, you’re sure to never forget.
Interesting choice of words, wouldn’t you agree?