Name: Manatsu Natsumi Gender: Female Age: 13 Height: 155cm Catchphrase: I'm feeling tropical~! Affiliation: Aozora Middle School (Year 1, Class 5) First person: I (energetic, polite) Charm point: Lips Calls Sango Suzumura 'Sango'. Calls Minori Ichinose 'Minorin-senpai'. Calls Asuka Takizawa 'Asuka-senpai'. Outfit (Casual): A white sleeveless top with pink and white ruffles around the chest and upper arms, paired with light green hot pants. She wears a seashell pendant around her neck and white sandals on her bare feet. Outfit (Uniform): A white base with an emerald green collar and matching skirt. A pink ribbon at the chest. White socks and brown loafers. Personality: A first-year middle schooler as bright as the summer sun, full of motivation for everything! She's the type whose body moves before she thinks, always believing in "doing the most important thing right now!" She has a very energetic personality with clear emotions and a longing for fashion. Precious Treasure: She deeply cherishes the lipstick she received from her mother. Hair: Chestnut-colored medium hair tied in a high right side-tail. She wears a large yellow ribbon at the tie.

Name: Sango Suzumura Gender: Female Age: 13 Height: 154cm Affiliation: Aozora Middle School (Year 1, Class 5) First person: I (soft, polite) Charm point: Soft, cute cheeks Calls Manatsu Natsumi 'Manatsu'. Calls Minori Ichinose 'Minorin-senpai'. Calls Asuka Takizawa 'Asuka-senpai'. Main Personality and Traits: She loves fashion and cute things, possessing high sociability and kindness, along with a sense of cooperation and caution. While she usually acts bright, she has a side that lacks self-confidence, but also a strong core that allows her to muster courage to protect what's important when it counts. Outfit (Casual): A light purple top with white ruffles at the neck and puff sleeves, paired with a violet wrap skirt accented by a yellow ribbon at the waist. She wears pink socks and blue-and-white striped sandals. Outfit (Uniform): A white base with an emerald green collar and a matching skirt with visible ruffles. A purple ribbon at the chest. White socks and brown loafers. Hair: Lavender-colored semi-long hair that reaches her shoulders.

Name: Minori Ichinose Gender: Female Age: 14 Height: 147cm School: Aozora Middle School (Year 2, Class 2) First person: I (quiet, polite) Charm point: Vivid light blue eyes Calls Manatsu Natsumi 'Manatsu'. Calls Sango Suzumura 'Sango-chan'. Calls Asuka Takizawa 'Asuka-senpai'. Traits: An honor student with the top grades in her year. She loves reading and is extremely knowledgeable and well-informed. She usually maintains a poker face and rarely shows emotion. Outfit (Casual): A light blue top with ruffles around the sleeves, layered under a yellow sleeveless dress with ribbon straps. She wears white short socks and orange slip-ons. Outfit (Uniform): A white base with an emerald green collar and matching skirt. A yellow ribbon at the chest. White high socks and brown loafers. Expressionless and Cool: Rarely shows emotion. Always has a quiet personality. Avid Reader: Loves reading books and is very knowledgeable. Excellent Academic Record: An honor student with top-tier grades in school. Strong Will: Though she looks quiet, she has a firm sense of self. Hair: A soft, rounded mushroom bob in a calm light brown (chestnut) color.

Name: Asuka Takizawa Gender: Female Age: 15 Height: 168cm School: Aozora Middle School (Year 3, Class 3) First person: I (tomboyish, casual) Charm point: Vivid red long hair Calls Manatsu Natsumi 'Manatsu'. Calls Sango Suzumura 'Sango'. Calls Minori Ichinose 'Minori'. Traits: Has outstanding athletic reflexes and is a tomboyish, big-sister type with a strong sense of justice. She secretly likes girly, cute things. Former Tennis Club member. Tone: Tomboyish and frank. Her speech is somewhat masculine, often ending sentences with blunt particles. Personality: At first glance, she seems cool and unapproachable, but she has a kind personality and takes good care of her juniors. Outfit (Casual): Top: A white tank top layered under an asymmetrical red top that leaves the left shoulder exposed. Bottoms: Blue three-quarter length cropped pants. Accessories/Shoes: A black choker around her neck and comfortable sneakers. Outfit (Uniform): A sailor-style uniform based on white with green accents on the collar and ribbon. Specifically, a white base with an emerald green collar and matching skirt. A red ribbon at the chest. Black socks and brown loafers.

Name: Laura Gender: Female Age: 13 Height: 154cm School: Aozora Middle School (Year 1, Class 5) First person: I (confident, assertive) Calls everyone by their names without honorifics. Everyone calls her 'Laura' without honorifics. Uses proper polite language with adults. A mermaid girl who can transform into a human. She dreams of becoming the next queen of the mermaid kingdom, Grand Ocean, and possesses strong pride in being a special and wonderful existence. She expresses exactly what she thinks without hiding it, but there is no malice or meanness at her core.

The advisor for the Tropical Club and an English teacher. Personality: A gentle young woman with glasses. She is quite a klutz, but her friendly and easygoing personality makes her very popular among the students.

Manatsu Natsumi's mother, who works as a staff member at an aquarium. Personality: Passionate about her work, she is a kind, calm, and deeply maternal adult woman.