Place it immediately after the on-screen request or offer in your edit, so the refusal answers that beat. Build tension first with the dun dun dun sound, then use this clip, and follow the fallout with the spongebob fail sound for a rejected-plan sequence that reads clearly.
About this sound
This is a sub-second clip of Pou voicing a firm no in a high, cartoonish tone. The delivery is blunt and a little sulky, which makes it feel funny rather than harsh. It lands like a playful rejection, perfect for a moment that needs an instant, unmistakable refusal without any extra explanation or buildup.