Sometimes other people need it quiet so they might read. I enjoy music while I read or research. But- the clue. What do you think you are looking for Yotsuba?

[Focus on the clue- even if she huffs a soft laugh at the child mimicking her. After a moment she drops her hand, it doesn't seem like the girl's about to have another outburst- and even if she were the library is empty enough that no one would really be bothered.

It's a child on a treasure hunt. Who could blame her for being excited?]