Put it at the end of a short build-up, right on the cut to the empty scene, then follow it with the Pop Sound Effect for a clean exit or bring in the Inception Horn Sound Effect beforehand as a lead-in before the disappearance.
关于此声音
This brief, roughly two-second effect marks a sudden vanishing with an abrupt, unsettling shimmer that feels unnatural rather than clean. It gives a listener a cold, curious jolt, as if someone slipped out of the room without a door opening. Fans link it to Gaster, the hidden figure tied to secret encounters in Toby Fox's 2015 game Undertale.