Yes! This is a really special Keyblade called sweet dream , you get in Kingdom Hearts Birth by Sleep, after you fulfilled the quest to collect all dessert types for Huey, Dewey, and Louie. This is quite hard cause you have to travel through all worlds, but every character can get such a Keyblade. It is just not very well known. This is the version for ventus, cause Aquas Keyblade has one more ice cream ball, during Terras blade has two more.
Long typing, short answer:
She made this blade, because it is one of Ventus official Keyblades, it was much more interesting then the standard blade, she fall in love with the blade design and the cosplay was crafted for a summer convention.