Hatake Kakashi is known as the Copy Ninja Kakashi due to his ability to mimic any jutsu. This ability was given to him by Uchiha Obito, allowing him to develop thousands of attacks.
So what if he uses Uzumaki Naruto's Sexy no Jutsu?
Without a doubt, Kakashi would make a very sexy female ninja. But I would rather not post something in Sanriotown that might lead to my being banned from the site. I know nothing is actually revealed in this cosplay, but Naruto fans know that Sexy no Jutsu makes the user... nearly, completely naked?
This is a cropped image from Photobucket. I'd quote the copyright owner, but I can't read the name...
EDIT: Thanks to Ellen for giving me the photographer, Willie Cheung's Flickr account!