A mannequin outfit is a outfit displayed at the shop window.
Customers with the mannequins style will see it and want it.
If you make an exceptionally matched outfit from the brand Alvarado, a cusotmer called Roccoca may come to your store and ask for the items. She appears to be a HUGE admirer of Roccoco and like Rococco uses some French in her sentences.
Make sure you dress the mannequin appropriate to the season (e.g summer/winter etc.) or Grace may come to 'tell you off'