Vanfic, also known as Vanfiction or Van Helsinki fanfiction, is the collective name for the stories found on fanfiction.net which detail aspects of Van Helsinki's life not seen in the film. Their canon status is disputed. All questions about the canon status of said Vanfics should be taken up with the director.
A complete list of the fanfiction stories on the wiki can be found here.
A complete list of published stories can be found here.