The name kiin comes from the Japanese onomatopoeia for a sharp, high ringing noise, a sound commonly used in animation and online video to suggest sudden quiet or stunned surprise. Short clips like this one circulate on soundboards because they are easy to recognise and easy to drop into a reaction, meme, or short edit without explanation. Its appeal has lasted because the effect is universal: almost everyone recognises that empty ringing feeling, so it can carry a joke or a dramatic beat in just a few seconds.