As a member of the student council, Hinamori Amu took up the Guardian position of Joker. Her task is to search for and purify X Eggs, X Characters as well as Mystery Eggs. Her Guardian Characters, Ran, Miki, and Su, help Amu with her task through a process called Character Transformation, which is enabled by the Humpty Lock and grants Amu special abilities depending on the guardian character.
Cute cosplay! She even has the eggs on her belt and her leg warmers are so adorable! Thanks again to Yukino for sending this in!