Novelist Eliza comes to the CUREtto Detective Agency to ask to work as a detective to get ideas for her next novel. Not long after that, the girls get a request to search for a missing cat.

Anna sees the mother of a client and thinks about her own mother.

While they help set up an exhibition at Hosho Art Museum, a glass slipper on display goes missing. Anna and Mikuru look for clues, certain that it was the work of the Phantom Thieves' Guild.