Place it at the punchline of a paper-toss scene, then follow it with Awkward Moment before an Anime Ahh closes the bit. For a bouncier classroom edit, follow it with Boing Boing instead, keeping the paper gag as the centre of the sequence.
關於此聲音
This is a very short voice clip, lasting under a second, built around Rikka's quick 'Ow' as a piece of paper is caught. The single yelp lands fast and sounds playful and a little flustered, like a small accident that is more funny than painful. It works as a light, cartoonish reaction, giving a scene a sudden jolt of cute surprise without slowing it down.