Put it near the end of a reaction edit, just after the revealing screenshot appears. Open with Bruh for disbelief, let this clip mark the turning point, then close with Emotional Damage to underline the consequence for the person caught out.
About this sound
This is a two-second Japanese voice line, spoken in a calm, flat tone that sounds like a quiet warning. It feels tense and knowing, as if the speaker has just realised something serious and is letting the silence do the work. That dry delivery makes it land as a sarcastic callout, turning an exposing post or an awkward confession into a moment that suddenly feels consequential.