Cheyenne O'Malley goes to Pine Heights Elementary with Allie Finkle, Sophie Abramowitz, Erica Harrington, Caroline Wu, Rosemary Dawkins, as well as the other students. She came from Canada, and started the kissing game and, once Mrs. Hunter stopped the fourth graders from playing it, began "going with" Patrick Day. Although Mrs. Hunter banned anybody in the fourth grade from "going with" anyone she still has a crush on Patrick for the remainder of the series and tries to get Mrs. Hunter to overlook the rule she had made (eg. She tries to get Mrs. Hunter to do Romeo and Juliet for the class play in book four, so that she can star as Juliet and Patrick as Romeo). She also likes to state th at she is a "semi-professional" actress, as she has starred in plays back in canada such as Anne Of Green Gables. She has a very strong, hateful dislike towards Allie, Erica, Sophie, Caroline, and Rosemary because she thinks they are completely and utterly immature (in other words, Allie and her friends like to play games and do things Cheyenne finds childish). Her friends are Marianne and Dominique, whom she calls "M and D". Some books tell that also Rosie, Elizabeth and Shamira are other people who are friends with Cheyenne, but M and D are her best friends.
Cheyenne's looks are not one of the topic discussed throughout the books, but can sometimes be described as having long, dark curly hair. She also has dark brown eyes and tanned skin. She mostly wears very fashionable clothing, such as brown suede zip-up boots and miniskirts, although her first appearance she was wearing a T-Shirt that read "Talent, Not Talk." It states that in book three, Cheyenne is as pretty as Sophie and looked confident.
Cheyenne is very stuck-up, cruel, bossy, girly, and according to herself "very mature". She likes to call boys and ask if they like her, then hang up. She is very spoiled and snobby and lashes out at Allie and her friends at any chance she gets. She is also portrayed as being extremely rude to adults, including her own mother (she shouted "shut up" to her once in a store because her mother didn't let her get $100 dollar genuine amethyst earrings).(Even though her mom did give in.) and Mrs. Hunter. Her personality is slightly comparable to Veruca Salt, the spoiled brat in Charlie and the Chocolate Factory.