- "Look, I'm not going to...solve your murder or whatever, so you can rest in peace. Sorry, not my scene. But I'll tell someone to come bury your bones or something. Okay?"
A Russian-American girl convinced that she's fat and unattractive, the protagonist of the story. She's an immigrant living with her mother and brother Sasha, attending the third worst private school in the state and trying to get by amongst rowdy classmates and boring classes by smoking and ditching with her friend Siobhan. After she finds Emily, Anya's life becomes a little more bearable.
- All of the Other Reindeer: Her backstory was being cruelly bullied by other children when she was younger, just because her family were poor Russian immigrants. Downplayed in the present—she occasionally gets laughed at by other students when something embarrassing happens to her, but she's not considered an outcast, even being able to hitch a ride to a popular kids' party.
- Big Sister Instinct: She might think her brother is a big pain, but she will still comfort and defend him from harm like when Emily frightens him after her true nature is revealed.
- Book Dumb: Her grades aren't so great but she is socially savvy.
- Disappeared Dad: Her father is not present and is implied to have divorced her mother, based on a comment from her mother that she uses child support to pay for "a good American private school".
- Hiding Your Heritage: Anya dislikes her lengthy Russian surname and pretends it's "Brown" when someone else asks her about it.
- Hollywood Pudgy: Invoked; Anya is so insecure she looks in the mirror and sees a fat girl, when in reality she's just got a curvy body type.
- I Am Not Pretty: Firmly believes she isn't attractive and that she never was attractive, even when several people insist otherwise.
- Jerk with a Heart of Gold: Anya has a definite mean side, including smoking, being rude to Emily and refusing to help her when they first meet, being ashamed of her Russian heritage, and believing Dima deserves to be beaten up everyday for acting so "fobby." However, she's actually a good person underneath who begins to wise up to why her behaviors are harmful after seeing them reflected in Emily, and she eventually quits them for good.
- She Cleans Up Nicely: She looks gorgeous wearing a low-cut top and short skirt at Matt's party, attracting the attention of at least two boys. Downplayed, because she's hardly unattractive in the first place to begin with (even if she thinks otherwise).
- Smoking Is Cool: She's seen smoking cigarettes in several scenes, fitting her desire to become a cool, popular teenager. At the end of the book, she gives it up, showing that she's starting to mature.
- Vitriolic Best Buds: With Siobhan, although she tends to take her jabs a little harder when in a bad mood, and especially if it concerns her crush on Sean.
- Weight Woe: Anya thinks she's fat and is strongly self-conscious about her weight. Apparently she was chubby when she was younger and was teased about it, which is where her self-esteem issues originate from.
- What You Are in the Dark: At Matt's party, she finds out that Sean, her crush, sleeps around with other girls and that Elizabeth, his girlfriend, lets him get away with it, being an Extreme Doormat. When Sean invites Anya to join him and another girl in the bathroom, she can't bring herself to hurt Elizabeth more by doing it. This turns out to be what makes her different from Emily—Anya is unwilling to hurt others to get what she wants, while Emily has no such qualms about doing so.
- Youthful Freckles: Has freckled round cheeks but not the cheerful persona.
- Zettai Ryouiki: In her school uniform she's between Grade A and Grade B, with stockings that go over her knees.
- "There hasn't been anyone but myself for so long."
A sweet little ghost girl whom Anya meets at the bottom of an old well, having died in 1917. She explains that she and her family were murdered by an unknown insane man and she fell while running from him. Ever since, she's been trapped in the well, at least until meeting Anya. After she comes home with her she's quite friendly and helpful. But she wants to stay Anya's friend forever...
- Adorkable: She's quite tiny and cute, and over enthusiastic to learn about Anya's world in more depth, Although that takes a dark turn.
- Cute Ghost Girl: She's spindly and has hair like a dandelion, making her more of a mousy cute.
- If I Can't Have You...: When she was rejected by her crush and saw him kissing the girl he was in love with, she barred the doors of his house from the outside and burned it to the ground with both him and his girlfriend inside it.
- Jacob Marley Apparel: She's stuck wearing the same jumper she wore when she died, and is even a little upset she can't wear more modern clothes.
- Non-Human Sidekick: She's one for Anya, being a ghost who is extremely helpful to her in school and her social life.
- Noodle People: Her ghost form is floaty, but even in life she was thin and flat and small. She later lampshades this after reading some magazines and learning her body type is a "Ruler".
- Not So Different: Near the end, when Anya calls her out on her evil behavior, Emily insists that Anya would have done the same thing if "she had held the match in her hands" and seen her crush with his love together. Anya denies it vehemently.
- Unreliable Narrator: On two instances: The boy she was in love with and supposedly engaged to, who supposedly died in World War I, actually didn't like her at all and she killed him after he rejected her for another girl. Leading into her second claim that she was chased into the well by a maniac—she was actually chased by an angry mob for said murder and fell down the well in the process.
- Vague Age: Most descriptions and her appearance in the story state she was a little girl at the time of her death (which was in 1917 if the story is set in 2011), while most (readers and Anya) assume her to be around Anya's age, particularly since she was engaged to be married; even in the 1910s, most people in America usually married in their late teens at the earliest. Except she was lying about being engaged; plus the photo of her that Anya finds in the newspaper report about her crimes shows her dressed in a rather juvenile fashion. Either way, her age isn't clear.
- Yandere: The book's cover implies she becomes this to Anya, but she actually was one to a boy she liked when she was alive, burning him alive with his lover.
- "I heard about you down in that freakin' well for two days! That's so badass."
Anya's best friend, although the two of them often have disagreements. She's an Irish girl with a load of terrifying older brothers and the only female in the school to wear pants. She's also caustic, another smoker, and a bit of a delinquent—despite this, she genuinely cares for Anya and the tries to help in her own way.
- A-Cup Angst: A tiny bit; Anya snarks at least that Siobhan is just jealous that no boy ever "talks to her boobs."
- Black Bead Eyes: Her character design, with bags underneath that make her look tired.
- Deadpan Snarker: This trait tends to tick Anya off, but Siobhan can't seem to help herself.
- Genre Savvy: She says that Anya's crush on Sean is like something out of a teen movie and questions if he's really being nice to Anya or to "her boobs." She's right about that.
- Hair Decorations: She has two hair clips.
- Jerk with a Heart of Gold: She's sarcastic, foul-mouthed, smokes (while bumming smokes off Anya), ditches class, and other delinquent behaviors, but she truly does care about Anya and defends her when anyone else picks on her.
- Lady Looks Like a Dude: Take out the Hair Decorations and one could mistake her as a boy for her short hair, clothes, tall frame, and thin and flat body.
- Massive Numbered Siblings: According to Anya, she has "about five thousand terrifying brothers".
- Nightmare Fetishist: She thinks Anya staying in a hole for two days is "badass" and is absolutely thrilled to hear she found a skeleton in it.
- Outnumbered Sibling: She has several brothers.
- Vitriolic Best Buds: With Anya, the two often trading barbs at each other.
Anya's crush. He's a handsome player on the basketball team who has a sure shot at becoming captain senior year. He's also dating Elizabeth Standard, which makes it hard for Anya to even get the nerve to approach him even if she wasn't feeling insecure. After meeting Emily, Anya just might have the courage to make her move after all.
- The Ace: He's hot, well liked, and a star on the basketball team dating one of the nicest girls in school. He's also fairly popular in the bedroom, too, unfortunately for his girlfriend....
- All Men Are Perverts: He's actually a major creep who cheats on his girlfriend (sometimes with his friends' girlfriends) and only pays attention to Anya because she's curvy.
- Black Bead Eyes: He's got these for his eyes, which give him a resemblance to Emily's crush.
- Nice Guy: He comes off as this to Anya at first, as an attentive boyfriend who's also quite friendly to her. He actually is a pretty bad boyfriend though, sleeping around and having Elizabeth keep watch.
Sean's girlfriend and one of the prettiest, most athletic girls in school—naturally she's like Anya's arch-rival in the story, especially in getting Sean's attention. Despite this, Elizabeth isn't a very mean girl, and as Anya eventually learns she has problems of her own.
- Alpha Bitch: Subverted and deconstructed.
- Beneath the Mask: She may seem happy and carefree all the time, but at Matt's party the truth comes out— she's a miserable girl with low self esteem who knowingly dates and aids a sleazebag.
- Disposable Fiancé: As Sean's girlfriend, this trope is played with; she initially seems to be the bland type compared to Anya, as pictured in Anya's own imagine spot, but Anya sees that Sean really does view her as disposable, or at least not worth being faithful too, and Anya can't bear to take that same view when she realizes this.
- Foreshadowing: When Anya falls and Elizabeth jumps over her to avoid getting tripped, she asks Anya if she is alright. This goes to show that she is a Stepford Smiler.
- Love Martyr: She loves Sean—or at least thinks she does—so she'll do anything to keep him—including showing that she's "cool" with him sleeping around by keeping watch while he does it.
- Mary Sue: In-Universe. Lampshaded by Anya—everything about her is utterly nice, making her wish Elizabeth would show just once that she can be imperfect too. She gets her wish when she sees how insecure Elizabeth is at Matt's party.
- Meaningful Name: Everything about her seems to be "standard" perfect traits for a rival love interest—thin, blonde, nice, athletic, and clear skin.
A little Russian boy whose family is friends with Anya's. He's nerdy, intelligent, small, and moved to America at a later point in his life than Anya—all making him a prime target for bullies. Anya, for her part, tries to ignore him, believing he deserves the bullying for being a "fobby creep" and not wanting more of the same.
- Adorkable: He's small and mousy, with usually a cheerful disposition despite his bullying—he's genuinely happy he can get a good education in America, even if it's hard.
- All of the Other Reindeer: He has a hard time in school; he even mentions how he can't go to gym anymore because the other kids broke his glasses so much and his family can't afford replacing them.
- Nerd: It gets him in a lot of trouble with his peers. He studies hard, is intelligent, spindly, gets turns of phrase wrong because of his Russian background, and he has no friends because of it all.
- "And what is so wrong with being a little fat? Back in Russia, being fat meant you were a rich man!"
Anya's unnamed mother who brought herself and her children over from Russia. An obese woman whom Anya seems terrified of turning into and embarrassed by, but is nonetheless a kind and caring mother who often worries about her daughter's moodiness and negativity.
- Big Beautiful Woman: Attractive and overweight and believes in this trope, stating that in Russia, being fat makes you look as though you have a lot of money.
- Foreign Cuss Word: When she falls down the stairs and hurts her ankle.
- Funny Foreigner: One of the reasons that she's so embarrassing to Anya is that she's sort of like this, such as when studying for the citizenship test and comedically flubbing who Benjamin Franklin was. She also can't speak English as well as Anya, leading to saying that in Russia being fat meant you were a "rich man."
- Good Parents: She's a sweet mother to Anya and Sasha.
- Gratuitous Russian: Provides all of it in the story, starting from what food she was making for breakfast. Oddly enough, she speaks in the Cyrillic alphabet initially and then the texts switches to a Romanization of Russian instead.
- Meganekko: Has big round glasses that emphasize her large eyes and looks endearing.
- "Anya! Come see this cool fossil I found today!"
Anya's little brother, a young boy with a fascination with dinosaurs and other large scary animals. He drives Anya up the wall with his habit of stealing her jewelry and burying it in the backyard so he can "discover" it later.
- Annoying Younger Sibling: Downplayed; he's mostly annoying for burying Anya's jewelry and being incredibly chipper when Anya herself is moody and depressed.
- Gender-Blender Name: Sasha is a girl's name in America; his family is from Russia, though, where it's a nickname for "Alexander."
- Youthful Freckles: He has them in much larger supply than Anya.