Put it in the middle of an edit, right after the setup line and just before the reaction lands, so it works as the punchline beat. Pair it with Anime Ahh for a second reaction, or follow it with Awkward Moment when the joke falls flat.
About this sound
This is a roughly four-second vocal clip of Hoshimachi Suisei rolling out one long, buzzing brrr in her bright, expressive voice, with the trill carrying the whole moment. It feels goofy and light, like a cartoon buzz meant to make a chat laugh rather than say anything serious.