Cath is the passionate and creative daughter of the noble Marquess and Marchioness of Rock Turtle Cove. She loves baking and dreams of opening a bakery with her best friend, Mary Ann, rather than conforming to her parents' expectations of a high-society marriage. She feels suffocated by the rigid social norms of Hearts but struggles to defy her family openly.

Jest is the mysterious and charismatic new court joker of Hearts. Clad entirely in black with a bell-festooned hat, he commands attention with his magical illusions and sharp wit. He possesses striking golden eyes that remind Cath of a strange dream she had, and he quickly forms a deep connection with her.

Hatta is a skilled hatmaker who crafts exquisite headwear with unpredictable magical properties. He dresses impeccably in a purple suit and matching top hat, hosting highly unusual tea parties for assorted creatures. He carries a deep fear of mental illness, which runs in his family, and searches for ways to avoid his prophesied fate by constantly moving.

The King is the cheerful but somewhat insipid ruler of the kingdom of Hearts. He frequently hosts lavish parties and avoids confronting unpleasant realities, such as the dangerous monster attacking his subjects. He is completely captivated by Cath and actively pursues a courtship with her, oblivious to her lack of reciprocal feelings.

Mary Ann is the housemaid for the Pinkerton family and Cath's closest confidant. Pragmatic and logical, she calculates the expenses and profits for their shared dream of opening a bakery. While she fully supports Cath's baking aspirations, she also recognizes the financial security a royal marriage would provide.

Cath's mother is a high-ranking noblewoman in Hearts who strictly adheres to court expectations. She is prone to extreme mood swings, alternating between warm affection and harsh, domineering demands. She expects her daughter to marry the King to elevate their family's social standing and dismisses Cath's baking aspirations entirely.

Cath's father is a timid nobleman renowned for his storytelling skills. He frequently defers to his wife's aggressive social climbing and refuses to contradict her when she reprimands Cath, failing to provide his daughter with the support she seeks regarding her bakery.

Peter Peter is the local pumpkin patch owner who recently received a knighthood. He treats others with hostility and suspicion, often assuming high-society members are mocking his lower-class background. He behaves harshly toward his wife while insisting her perpetual illness is simply food poisoning, guarding his property fiercely.

Lady Peter is Peter Peter's diminutive wife, who recently earned a knighthood for their family by winning a massive pumpkin-eating contest. She constantly appears pale, sickly, and covered in perspiration, leading others to worry about her health while her husband keeps a tight watch over her actions.

Lacie, Tillie, and Elsie are mysterious, ghostlike figures residing in the mythical treacle well. Appearing as young children with ancient, coal-black eyes, they possess seemingly boundless knowledge about the world. They provide healing treacle to desperate travelers in exchange for unusual, highly specific payments.

Raven is a literal raven who serves as Jest's constant companion. He speaks exclusively in rhyming couplets and assists the joker with his tricks, distractions, and travels throughout the kingdom. He provides a watchful, foreboding presence wherever Jest goes.

Cheshire is a disappearing cat known for his wide, distinctive smile. He materializes frequently to offer Cath information, advice, or gossip about kingdom events. While he provides useful news, his cryptic manner of speaking often leaves Cath frustrated.

The Duke of Tuskany is an awkward and lonely nobleman whom Cath initially misjudges as arrogant. He holds the lease to a cobbler shop that Cath hopes to rent for her bakery and harbors a deep, unrequited affection for Margaret Mearle.

Margaret is Cath's childhood friend who frequently imposes nonsensical morals on those around her. She acts haughty and critical, particularly toward Duke Pygmalion's awkward affections, viewing herself as highly proper.

The Caterpillar is a local cobbler in Hearts who is preparing to close his shop. He encourages Cath to lease his building for her bakery, directing her to his landlord, the Duke of Tuskany.

Haigha is a march hare who frequently attends Hatta's unconventional gatherings. He serves as an associate of Hatta and Jest in their activities and helps host the strange events in the woods.

The Turtle is a timid resident of Hearts who participates in social gatherings and serves as an adjudicator for the Turtle Days Festival's baking contest. He is easily frightened and tends to freeze completely when danger approaches.

The Lion is a brave creature who attends Hatta's secret tea parties. When a terrifying monster crashes the gathering, he fearlessly throws himself into danger to protect the other guests.