Dead little mean girl

"A proud geek girl, Emma loves her quiet life on the outskirts, playing video games and staying off the radar. When her nightmare of a new stepsister moves into the bedroom next door, her world is turned upside down. Quinn is a queen bee with a nasty streak who destroys anyone who gets in her way. Teachers, football players, her fellow cheerleaders--no one is safe. Emma wants nothing more than to get this girl out of her life, but when Quinn dies suddenly, Emma realizes there was more to her stepsister than anyone ever realized"--Provided by publisher.