Bad Girls Don't Die by Katie Alender
Alexis Warren is comfortable with her loner status. She's a pink-haired rebel more at home behind the camera than in the halls of high school, and she likes it that way. At home, she easily navigates her constantly-working mother and her distant father. But she and her doll-obsessed little sister Kasey are close, the only real constants in each other's life.
But something is wrong with Kasey. Her sweet, shy little sister has been acting weirder than usual. She's been saying things Kasey would never say, stealing classmate's genealogy projects from school. Dangerous accidents seem to happen around her, and perhaps most frightening of all, half the time Kasey's pale blue eyes have turned a frightening stranger green.
Alexis is the only one who realizes just how dangerous Kasey has become, and she's the only one who can stop her little sister before it's too late. But what if she can't stop the evil and save her family without stopping Kasey, too?
First and foremost, this book succeeds as a genuinely creepy, really scary ghost story. It's actually frightening, and I like that in a ghost book. Some of the plotting is overly simple and predictable--while one plot twist evaded me entirely, I predicted most of the others long before they happened. And the ending was a little too neat for my tastes.
But Alexis is chock-full of personality, the ghost story is scary, and the writing is compelling. I absolutely enjoyed, and stayed up to finish.