Emily Asher isn't the only Jackson High other cheerleader who stirs up trouble for Lena.
According to all the guys, Savannah Snow is the hottest girl in school. "The standard by which all other girls at Jackson were measured" (9.02.42). She may get Ice Queen every year and be cheerleading captain, but she sure isn't the brains of the group. She's like Teen Talk Barbie, who infamously said, "Math class is tough."
Still, she has a lot of influence. She has all the guys clamoring for her. She recruits plenty of students into the Guardian Angels, the club that's determined to get Lena kicked out of school. And she draws the fake birthmark on her face to mock Lena on Halloween. Also, the hotter and more popular Savannah gets, the meaner Emily gets to try to keep up.
Eden Westerly definitely gets hated on by all the other cheerleaders. Ethan just about sums it up when he says, "Her thing was trying to be different, except for, I guess, the part about being different. Nobody was different at Jackson" (9.12.35).
And in any case, she's only different than the other girls on the outside. Basically, she likes to dye her hair different colors. It never quite works out the way she would like it to, though. Usually, she just ends up with a comment like this one from Savannah: "You looked like a skunk" (2.11.161). Yeah? Well we bet Savannah smelled like one.
Charlotte Chase is the chunky cheerleader who doesn't quite fit in. As Ethan says, "If Eden was second string, Charlotte was third" (9.12.36).
All these bully ladies don't influence the overall plot that much, but they do flesh out the Jackson High student body. To comfort Lena, Ethan tells her, "Emily will get a new car and Savannah will get a new crown and Eden will dye her hair a new color and Charlotte will get, I don't know, a baby or a tattoo or something, and this will all be ancient history" (9.12.82). He's more right than he thinks. With everything else Ethan and Lena have to deal with (you know, the fate of the world and all), these girls are the least of their worries.