Prompt: Trick-or-Treat
"It's a holiday," Erza explained to her enraptured audience, "where children dress up as monsters, go to strangers houses and ask 'trick-or-treat', and if the owner doesn't provide treats, the children play pranks on them."
Erik and Sorano seemed far too invested in the pranking portion of that explanation, to Macbeth's observation, and Meredy with the treats part.
"I thought it would be a good way to use all of the leftover treats we made," Erza continued, sweating slightly under Jellal's rather judgmental gaze over the baking spree she and Richard had gone on, "and for us it'd be more like a party, since we're already well past the holiday and we're adults, but we can still dress up!"
To Macbeth's surprise, Jellal agreed, "It'd be a good way to use up some things before they go bad, so let's do it."
Macbeth saw little point in dressing up when the world already believed them to be monsters, but he accepted the mask Erza handed him from her stores all the same.