I know I have a lot of characters to keep track of. Hopefully, this list will help you if/when you get confused about who's who. 🤓
The list includes any character mentioned by name, or who have dialogue.

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       A:
Aaron Donoghue – Olivia's Minnesota friend
Adrianna Winter – the headmaster's personal secretary
Alex Casini [Alexander] – Olivia's uncle (mentioned only)
Allison Lawrence-Price – senior classmate
Amelia LoPinto [the Amelias] – gossipmonger and senior classmate
Amelia York [the Amelias] – gossipmonger and senior classmate
Anniqa – Olivia's therapist
Arlen Ritter – Olivia's original cotillion escort (mentioned only)
Arwen Donoghue – Aaron's older sister (mentioned only)
Atticus Bartlett – senior classmate

       B:
Bambi – Milgram's enforcer
Beefy doorman – employee at the Little Shubert Theater
Mr. Birch – teacher and Josephine's father (mentioned only)
Blaine Montgomery – Josephine's boyfriend and senior classmate

       C:
Carlotta Casini – Olivia's great-grandmother (mentioned only)
Cash Montclair – senior classmate (mentioned only)
Charly Andrew [Charlene] – Sebastian & Maggie's mother
The chauffeur – Ricky's horrible driver
Christian Casini – Olivia's younger cousin
Christina Davenport Casini – Olivia's mother
Claire Chang – senior classmate
Claudia Banks [Teresa] – Ricky's flirt and senior classmate
Coco van der Meersch [Constance] – Olivia's childhood friend
Cole Sawyer – senior classmate
Colleen Fallon – Olivia's great-aunt (mentioned only)

       D:
David – Roxie's supervisor at Fashion Week (mentioned only)
DJ – Lincoln's old friend from Miami (mentioned only)
Dr. Goatee – Olivia's second E.R. doctor
Doorman – doorman at Olivia's building
Miss Dover – cotillion dance teacher

       E:
Elaine Magnussen – Roxie & Lincoln's mother
Elizabeth Stark von Linden – Ricky's mother (mentioned only)
Élodie Deneuve – Olivia's aunt in France (mentioned only)
Emmy Fitzpatrick – Fashionista and senior classmate

       F:
Mr. Finlay – AP Science teacher
Florencia Valence – Coco's socialite friend (mentioned only)
Frank – employee at the Little Shubert Theater
Fred Stark von Linden [Frederick] – Ricky's father

       G:
Gabriela Carr – Olivia's bully and senior classmate
Gangly doorman – employee at the Little Shubert Theater
Gatsby – Coco's cat
Georgina van der Meersch – Coco's mother
Fr. Gilbert – PE teacher (mentioned only)
Guy Whitener [Gerard] – Sebastian & Maggie's father

       H:
The Henley girl – retracted from the cotillion (mentioned only)
Henry Ha – Blaine's friend and senior classmate
Holan Reeves – the Stark von Linden's attorney
Mrs. Holbrook – Spanish teacher (mentioned only)

       I:
Isaac – Roxie's ex-boyfriend

       J:
Jack – Maggie's pet rabbit
Jailene Bernstein – Fred's personal secretay
Dr. James Caffrey – E.R. doctor and Elaine's love interest
Jamila – the Davenport Casini's housekeeper
Jane – Roxie's lawyer (mentioned only)
Jasmine – Roxie's old friend from Miami
Jason Takanashi – Claire's best friend and senior classmate
Jerry – employee at the Little Shubert Theater (mentioned only)
John Casini – Olivia's maternal grandfather
Jonathon Pryor – Sebastian's uncle's fiancé
Josephine Birch – Olivia's friend and senior classmate
Julian Loreto – Ricky's tattoo artist
Juniper Malone – Lincoln's "date"

       L:
Lincoln Magnussen – Roxie's brother
Lita – the Whitener's housekeeper and nanny
Liz Arthur – Elaine's previous client (mentioned only)
Lorraine Davenport – Olivia's paternal grandmother

       K:
Karen Lowe – previous bullying victim (mentioned only)
Keiko Magnussen – Roxie & Lincoln's stepmother
Kyle Betley – Lincoln's old friend from Miami

       M:
MacKenzie van der Meersch – Coco's sister-in-law
Maggie Whitener [Margaret] – Sebastian's younger sister
Fr. Marcus Palmer – the school's deputy headmaster
Martha Casini – Olivia's maternal grandmother
Martin Donoghue – William's Minnesota friend
Matthew – Blaine's friend and senior classmate
Michael Andrew – Sebastian's uncle
Mickey Solano [Michaela] – Roxie's old friend from Miami
Mikhail - the Stark von Linden's butler
Milgram – Fred's client (mentioned only)
Milton Davenport – Olivia's paternal grandfather
Mitchell Hagen – senior classmate
Monroe Ambrose – Coco's second cotillion escort

       N:
Nadine Hardt – Fred's girlfriend
Nicolette Keaton – Olivia's bully and senior classmate
Ofc. Novak – officer at Ricky's hearing

       O:
Olivia Davenport Casini – main female character
Mrs. O'Malley – AP Economics teacher (mentioned only)

       P:
Fr. Parisi – Olivia's family priest (mentioned only)
Paul – Coco's first cotillion escort (mentioned only)
Sis. Paulsen – school's Administration worker
Photoshoot director – director of Fred's photoshoot
Porceline Nichols – Olivia's bully and senior classmate

       R:
Rebecca Banks – Claudia's cousin and senior classmate
The receptionist – the receptionist at Fred's office
Fr. Richard Correll – the school's headmaster
Ricky Stark von Linden [Frederick] – main male character
Robert van der Meersch – Coco's father
Roxie Magnussen [Rose] – Olivia's new friend
Ofc. Russo – officer at Ricky's hearing
Ryan O'Neill – Christina's love interest

       S:
Samantha Wells – Coco's maternal grandmother
Dr. Sara – Roxie's therapist (mentioned only)
School board woman – graduation announcer
Sebastian Whitener – Ricky's best friend

       T:
Tattoo clerk – clerk at the tattoo parlor
Taylor Casini – Olivia's ex-aunt (mentioned only)
Terrence Magnussen – Roxie & Lincon's father
Tori Hirsch – Coco's older half-sister
Tye – the Stark von Linden's private chef

       W:
Mr. Wallace – History teacher (mentioned only)
William Davenport Casini – Olivia's father
Mr. Winkler – Fred's client (mentioned only)