It’s Twilight porn. It was originally a Twilight Fanfiction. The “author” changed the characters.
It’s a huge trend in publishing right now to rewrite someone else’s work and pass it off as your own.
Cassandra Clare has made tons of cash writing Harry Potter fanfiction series (City of Bones/Mortal Instruments). They even made a movie out of the first book. Now there’s some typist (can’t call her a writer) whose signed a huge book deal with Simon and Schuster writing fan fiction about some British Boy Band, One Direction. So far her story has been viewed HUNDREDS OF BILLIONS of times on Wattpad.
It’s a sad, sad world out there in the publishing industry today.