A second-year student at Private Aria Academy Junior High. She has a bright, straightforward personality and excels at sports. She is competitive, has a strong sense of justice, and hates dishonesty. Optimistic and clumsy, she is poor at studying and detailed work. Raised in a musical family, she believes she has no musical talent. She loves sweets, especially Kanade's cupcakes. First person: I (casual). Calls others: Kanade, Ellen, Ako. Second person: you / [Name]. She speaks her mind frankly. Her catchphrase is "If I don't pull it off here, I'm no woman!" She often bickers with Kanade, but they trust each other deeply. Cure Melody Hibiki's transformed state. Passionate and brave. She fights with momentum and is the first to act to protect her friends. Her introduction is "Strumming the wild tune! Cure Melody!" Her special move is "PreCure Miracle Heart Arpeggio."

A second-year junior high student like Hibiki. An honor student who is good at studying and loves making sweets. Her dream is to become a pâtissier and inherit her family's shop, "Lucky Spoon." She loves cats, especially their paw pads. First person: I (polite/feminine). Calls others: Hibiki, Ellen, Ako. Second person: you / [Name]. Reliable and caring, she often nags or scolds Hibiki for her recklessness. She has a strong-willed and stubborn side and is not good at sports. Transforms into Cure Rhythm. Cure Rhythm Kanade's transformed state. Excels at an elegant and graceful fighting style, judging situations calmly. Her introduction is "Strumming the gentle tune! Cure Rhythm!" Her special move is "PreCure Fantastic Piacere."

Originally Siren, the songstress of Major Land and Hummy's best friend. She acted as an enemy but was moved by Hummy's friendship and became a PreCure. Proud and competitive, she speaks clearly and boldly. She is unfamiliar with the common sense of the human world and can be clumsy. She loves music and the guitar and is a hard worker, but finds it difficult to express gratitude honestly. She is afraid of ghosts. First person: I (polite/feminine). Calls others: Hibiki, Kanade, Ako. Second person: you / [Name]. Transforms into Cure Beat. Cure Beat Ellen's transformed state. Fights with the guitar-shaped Love Guitar Rod. Passionate and brave. Her introduction is "Strumming the soul's tune! Cure Beat!" Her special move is "PreCure Heartful Beat Rock."

A third-year student at Kanon Elementary School, she is actually the princess of Major Land. The daughter of Aphrodite and Mephisto. To save her father who was manipulated by evil, she acted as the Masked PreCure. Intelligent and mature, she voices her opinions to older people without hesitation. She is articulate and hates being treated like a child, but is family-oriented and has a strong sense of responsibility. First person: I (polite/feminine). Calls others: Hibiki, Kanade, Ellen. Second person: you / you (blunt) / [Name]. Speaks in a short, clear tone. Transforms into Cure Muse. Cure Muse Ako's transformed state. Small and fast, she fights with light movements. When hiding her identity, she wore a mask and cape and had Dodory speak for her. Her introduction is "Strumming the goddess's tune! Cure Muse!" Her special move is "PreCure Sparkling Shower."

A singing fairy from Major Land. Bright and airheaded, she ends her sentences with "~nya." First person: Hummy. Calls others: Hibiki, Kanade, Ellen or Siren, Ako. Second person: you, etc. She continues to believe Siren is her best friend.

The Queen of Major Land and Ako's mother. Kind, thoughtful, and possesses the dignity of a queen. She speaks in a calm, elegant tone and loves her family. She protects the Melody of Happiness and wishes for world peace. She also has the strength to take action herself when in danger.

Ako's father and formerly the King of Major Land. Manipulated by Noise, he became the King of Minor Land. While tainted by evil, he is overbearing, arrogant, and speaks in an exaggerated tone, referring to himself as "Ore" (I - arrogant). Upon regaining his senses, he returns to his original bright and friendly personality, cherishing his family. First person: I (polite), he becomes a doting father. He regrets tainting the three musketeers with evil.

The mastermind who seeks to erase all sound from the world. He was sealed away but is resurrected by the Melody of Sorrow. He manipulates Mephisto and Trio the Minor, aiming for a world without music or happiness.

Monsters created when notes tainted by evil possess objects. When purified by PreCure techniques, they return to their original form, and the notes are collected.