This is a girl who hates Ethan because her perfect hairdo was ruined when she was with him. And more importantly, she hates Lena because she's, well, different. In fact, if Lena didn't have Sarafine to deal with, Emily would be her main antagonist. But Emily's too lame to receive that title—she's just your typical bully, jealous of Lena who is prettier, smarter, and all around awesome-r than Emily. Emily may have power, but it's just power of the social kind, and tenuous at best. That kind of power probably won't last after graduation. Lena could wipe the floor with Emily's pom-pons any day.
Still, Emily does all she can to make Lena's life difficult. She takes her journal and taunts her. She's behind the prank at the Winter Formal that leaves Lena's dress drenched and ruined. And much to our dismay, she never really gets any sort of comeuppance. We last see her making out with Larkin at Lena's surprise party. She gives a present to Lena and pretends to be her best friend, but it's all because of Ridley's control. Or is it? If Lena were to become the queen bee of Jackson High, we're sure Emily would be nipping at her heels.