Instant Karma by Marissa Meyer

In this young adult contemporary romance, a girl is suddenly gifted with the ability to cast instant karma on those around her—both good and bad.

Chronic overachiever Prudence Daniels is always quick to cast judgment on the lazy, rude, and arrogant residents of her coastal town. Her dreams of karmic justice are fulfilled when, after a night out with her friends, she wakes up with the sudden ability to cast instant karma on those around her. Pru giddily makes use of the power, punishing everyone from public vandals to karaoke hecklers, but there is one person on whom her powers consistently backfire: Quint Erickson, her slacker of a lab partner and all-around mortal enemy. Soon, Pru begins to uncover truths about Quint, her peers, and even herself that reveal how thin the line is between virtue and vanity, generosity and greed . . . love and hate.