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However, with the use of THE INTERNET(tm), I have deduced that the piece was most likely originally made and uploaded by a fairly unknown Japanese artist who goes under the name of Kitanti! :D ...Pixiv doesn't like us westerners that much though (mostly because we steal their art and don't credit them), and thus it's difficult for me to double check his profile there. Not letting me access it.
But most 'boorus out there credit this Kitanti person! Oh internet, you can be so useful sometimes!