Place it at the end of a reaction sequence as the final verdict, after a vine boom sound for the shocking reveal and before a classic fart sound if the joke continues into pure silliness for younger viewers.
关于此声音
This is a very short mouth-made raspberry effect, a lip-blown pppptttt burst lasting under a second with no words or music. It feels cheeky, dismissive and instantly funny, like a playful rude reply or a kid blowing a raspberry instead of arguing back.