PRIVATE WAREHOUSE 
This is a set of clothes or accessories for figures.
From Good Smile Company:
The Nendoroid More series was created to make Nendoroids even more enjoyable! Next up in the series is Dress Up Gothic Lolita! The line-up includes a purple one piece dress with ribbon and a black one piece dress with hair decoration for female characters, as well as a black classical prince outfit with top hat and a purple dolly prince outfit with teddy bear for male characters. Be sure to add them to your collection!
Note: Images are for illustrative purposes only. No Nendoroid head parts are included with this product. May not be compatible with certain Nendoroids depending on the character design.