Place it immediately after the confusing statement in your edit, then follow with the anime wow sound for a second shocked reaction, or precede it with the dun dun dun sound to build a mock-serious reveal before the response lands.
About this sound
This two-second voice clip captures a young woman blurting out 'girl, wtf is you talking about' in a flat, incredulous tone. It lands as pure secondhand confusion, turning a nonsense statement into an instant laugh. The delivery feels rude, baffled and completely unconvinced, like a reality check delivered mid-conversation.