12 Days of Christmas was an event way back in Winter 2010/2011. A player had to collect 12 items, one item daily, and receive a beautiful reward at the end.
The final reward outfit is called Sugar Plum Fairy Outfit. Each Reward Item is named separately, but all have Sugar Plum Fairy at the beginning of every name. The outfit consists out 6 items total.
All items, save for all reward clothes and wig, can be bought in It or Miss from other players. Starting from 29 November 2013, all reward items are Star Imports items and can no longer be bought via It Or Miss.