Miss Mayhem (Rebel Belle #2) by Rachel Hawkins

Life is almost back to normal for Harper Price. The Ephors have been silent after their deadly attack at Cotillion months ago, and best friend Bee has returned after a mysterious disappearance. Now Harper can return her focus to the important things in life: school, canoodling with David, her nemesis-turned-ward-slash-boyfie, and even competing in the Miss Pine Grove pageant.

Unfortunately, supernatural chores are never done. The Ephors have decided they’d rather train David than kill him. The catch: Harper has to come along for the ride, but she can’t stay David’s Paladin unless she undergoes an ancient trial that will either kill her . . . or connect her to David for life.