The only thing that makes St Teresa's Preparatory School for Girls bearable for Jane is her best friend Ally. But when Ally changes into a whole different person literally overnight the fall of their senior year, Jane's suddenly alone - and very confused. Turns out, Ally has sold her soul in exchange for popularity - to a devil masquerading as a sophomore at St Teresa's! Now it's up to Jane to put it all on the line to save her friend from this ponytail-wearing, cupcakenibbling demon...without losing her own soul in the process.