This a cool blue Ballerina costume.
This is how to get it.
Hair: Icarus costume, or a non member alternative, the Prom Queen hair. (75 credits.)
Top: Blue Prom Queen top. (75 credits.)
Skirt: The skirt from the princess on Poptropicon: Line forms Here.
Earrings: Icarus costume (members only.)
Lips: The New You shop.