The SDM crew and the idiots at the back I get, who are the three in the middle?
Apple Bloom (yellow), Sweetie Belle (off-white) and Scootaloo (orange), collectively known as the Cutie Mark Crusaders. According to the DeviantArt commentary, they're not meant to be subbing as any Touhou characters. Rather, they're just attempting to earn their cutie marks, this time in...er, Fairy-Maiding. And failing with their usual flair.