Place this clip as the final reaction beat after the setup line, then follow a second take with another onii-chan voice clip for a call and response. In longer anime edits, precede it with the Tuturu sound to build a character chain before the punchline lands.
關於此聲音
This two-second voice clip has Hololive English VTuber Gawr Gura saying onii-chan in a high, sweet and slightly shy delivery. It feels cute and teasing at once, playful rather than serious. The line came from a livestream moment prompted by a red Super Chat request, which is why fans treat it as a prized fan-service reaction.