Because TN willed it to be seeing as they have been fans of Glee since day one. There could only be one way to show their affections and that would be to make Christie look like TN's favorite Glee member.
What's underneath those clothes might if they belonged to Rachel. *cough* Oh and reminds me of the porn series Innocent High, oh the glorious fap... I mean, educative material.
Surely there must be some outfits that Kurt wore that seems a bit less effeminate or something that doesn't dwell too far on the effeminate category. XD