Written for the prompt 'Any fandom, any, a little shop that wasn't there yesterday and won't be there tomorrow' at the Three Sentence Ficathon 2018. This is a six-sentence version.
The Pop-up Shop: shallowness
Mahoney is on her way to open up the Wonder Emporium from the Mutant's place with the beginnings of a sonata or maybe more in her mind. It emerged after she said goodbye to him, making her barely notice the bus ride. Suddenly afraid the idea is too restless a thing and the succession of notes that came to her will fly right back out of her mind if she doesn't get it down, she reaches inside her purse for a sheet and realizes it's her date purse. She looks up in consternation. But there, out of the corner of her eye – and she can hear Mr Magorium saying that sometimes that's the best view – she spots a tiny music store that she knows she's never seen on this street before and suspects she'll never find again. Mahoney smiles, a twinkle in her eye, and rushes out of her seat.