This one was easy to get into. I'm rounding up to four stars. 
 First, what I loved: Anna. She is pretty damn awesome. Tragic, scary, strong. Sympathetic, yet you also wouldn't really want her hanging around. She ain't Caspar the Friendly Ghost. I loved all of the ghost story aspects, every scene she was in, her relationship with Cas and her uneasy relationship with everyone else. 
 In the middle: Cas, the narrator. I got Cas, his drive, what keeps him going. I also get why he is so enthralled with Anna. There were lots of times I wanted a bit more on why he is the way he is and his mom/adult figures let him do what he wants, which brings me to: 
 What didn't work for me: basically every adult except for Morfran. I don't get the mom. She is just barely there until the end, yet she willingly uproots them and moves wherever Cas wants to fight ghosts without argument. I mean, if she had been more forceful, like a really violent stage mom, that would have made more sense ("You WILL be the best Chosen One ever! Go practice stabbing stuff.). 
 So, you do have to suspend some disbelief. If I was a teen reading this, the adult's lack of involvement (from parents to teachers to police) probably wouldn't have bothered me as much. That said, it still drew me in and I had to finish it, so I will be looking for the next book from this author.