Don't Feed the Monster

"...if there's anyone reading this, and if anyone wishes to risk his life to save mine, the most important thing to remember is that you should
never
ever
feed the monster."

Brooklyn Anne Jones leads a normal teenage life. She goes to school, takes piano lessons, and of course, has a best friend: Christine. Christine is outgoing, creative, and an all-around good person. So, when Christine starts writing a story and posting it online, naturally, Brooklyn reads it. As she follows Christine's story online, Brooklyn sees some strange parallels between reality and Christine's book, and she realizes there is a dark secret buried underneath it all.
Is the real world as dangerous as Christine's fictional one?