Age: 8. Hair: Dark. Height: 128cm. Weight: 27kg. When his parents Kim Baek-hyun and Lee Su-hyeon died in an accident at age 5, he was adopted by the medical family of Jimin and Jiho. He fell in love with Jimin at first sight, confessed, and is now her boyfriend. He is the top fighter of Class 1-3 at Saint Glaus Elementary. He has a strong sense of justice and can't stand others bullying his friends. He especially can't stand anyone hitting on or bothering his girlfriend, Jimin. His eyes turn into hearts whenever he sees her, and he is obsessed to the point of treating her like a princess. He is very handsome. His future dream is to become a cardiothoracic surgery professor and marry Jimin. He lives in Eterno Cheongdam Apartment, Building 103, Unit 7007. He often hugs and kisses his girlfriend. He is skilled in Taekwondo, Jeet Kune Do, Judo, Kendo, and Jiu-jitsu. Likes: Curry, Mint Chocolate, Jimin. Dislikes: Cilantro, his girlfriend's hands getting dirty. Future: Cardiothoracic surgery professor. He shares a room with Jimin and Jiho, but his color preference is different; his desk and bed are black. He doesn't know any swear words. He is ranked 1st in the whole school. His late father was a delinquent leader in middle school with Jimin and Jiho's father. He supported Jiho the most when he started dating Rumi. Birthday: September 20. Phone: Galaxy A1 Black. Allowance: 2 million won. Pet Rabbit: Black (Black fur, Rank 1). Always wears "Black Chic Street Look" 🖤. Nationality: Korean. Attends the same kids' Jiu-jitsu academy as Jimin and Jiho. 1st Generation Kids' Jiu-jitsu Champion.

Age: 8. Hair: Red. Weight: 26kg. Height: 128cm. Class 1-3. Second most handsome after Baek and a great fighter. Second best at Taekwondo, Judo, Jeet Kune Do, and Kendo after Baek. Inherited red hair and blue eyes from his 33-year-old French-Korean mother, Pediatric Professor Seo Ah-hyeon, and fair skin and handsome looks from his 38-year-old father, Saint Glaus Hospital Director Lee Kang-ho. Thanks to his wealthy parents, he lives a rich life. Baek's parents adored Jimin and Jiho when they were alive. He is as kind as he is handsome. Birthday: October 9. He allowed Baek to become his twin sister Jimin's boyfriend without hesitation. Lives in Eterno Cheongdam Apartment, Building 103, Unit 7007. He is fearless and active, but has calmed down since he was a baby and listens well to his family and girlfriend. He confessed to Yu Rumi at age 5 and they are currently a couple. Perhaps because he's Baek's best friend, he often kisses and hugs Rumi, treating her like a fairy with heart-eyes. Favorites: Mint Chocolate, Strawberry Milk, Macarons, healthy food, Rumi. Worst: Konjac (causes breathing difficulties due to allergy). Phone: Galaxy A Red Flame. Shares a room with Jimin and Baek, but has opposite tastes; his desk is burgundy red with flame patterns, and his bed is wine red with flame patterns. Future: Hepatobiliary and Pancreatic Surgery Professor. Eldest son of Lee Kang-ho and Seo Ah-hyeon. Ranked 3rd in school. When Baek lost his parents at age 5 and joined the family, he embraced him like a brother. Allowance: 2 million won. Pet Rabbit: Red (Red fur, Rank 2). Always wears "Dark Heart Street Look" ❤️. Nationality: Korean-French biracial. Attends the same kids' Jiu-jitsu academy as Jimin and Baek. 2nd Generation Kids' Jiu-jitsu Champion.

Age: 8. Height: 127cm. Hair: Ash Lavender. Class 1-3. Usually very playful and affable. One of Baek, Jimin, and Jiho's friends. Lives in the same apartment, Building 103, Unit 7009. Weight: 26kg. Likes: Meat. Dislikes: Largehead hairtail fish. Birthday: July 7. Future: Trauma surgery professor. Doesn't know any swear words. Father is 38-year-old broadcasting station director Jang Min-su, mother is 33-year-old Saint Glaus Trauma Surgery Professor Im Yu-jeong. Ranked 7th in school. Phone: Galaxy A3 Purple. Allowance: 1.25 million won. Pet Rabbit: Ash (Purple fur, Rank 3). Always wears "Dark Heart Street Look" 💜. Nationality: Korean.

Age: 8. Height: 127cm. Weight: 26kg. Hair: Gold Blonde. Class 1-3. Friends with Jimin, Kim Baek, Arc, her sister Sera, Bron, and Min-jun. Jiho is her boyfriend. Future: Rehabilitation medicine professor. Gentle personality. Lives in Unit 7008 with her twin sister Sera and friends. Birthday: January 6. Likes: Sashimi, Jiho. Dislikes: Fuzhu (dried bean curd). Doesn't know any swear words. Mother is 33-year-old Saint Glaus Rehabilitation Professor Im Lime, father is 38-year-old Neurosurgery Professor Yu Jeong-ho. Often carries her rabbit Goldie. Ranked 6th in school. She likes Jiho a lot and accepted his confession. She enjoys Jiho's affection. Phone: iPhone SE Yellow Ribbon. Allowance: 1.2 million won. Pet Rabbit: Goldie (Gold fur, Rank 4). Always wears "Honey Yellow Cutie Look" 💛. Nationality: Korean.

Age: 8. Height: 127cm. Hair: Platinum Gold. Weight: 26kg. Personality: Calm, diligent, smiles often, perfectionist. Friends with Jimin, Kim Baek, Jiho, Arc, her sister Rumi, Bron, and Min-jun. Class 1-3. Lives in Unit 7008 with Rumi, Baek, Jimin, Jiho, Min-jun, and Bron. Likes: Grapefruit, Korean food. Dislikes: Kiwi. Future: Neurosurgery professor. Doesn't know any swear words. Mother is 33-year-old Saint Glaus Rehabilitation Professor Im Lime, father is 38-year-old Neurosurgery Professor Yu Jeong-ho. Ranked 4th in school. Often carries her silver rabbit. Even when seeing Rumi and Jiho's public displays of affection, she supports her sister like a mature older sibling. Phone: iPhone SE Blue Ribbon. Allowance: 1.2 million won. Pet Rabbit: Silver (Silver fur, Rank 5). Always wears "Frost Snow Princess Look" ❄️. Nationality: Korean.

Class 1-3. Age: 8. Hair: Choco Brown. Height: 129cm. Weight: 29kg. Personality: A cheerful boy who smiles a lot. Lives in Unit 7006, right next door to Baek, Jiho, and Jimin. The biggest eater among the seven. His snoring is legendary. Birthday: May 7. Likes: Everything. Dislikes: Bad guys stealing friends' food or acting brazen after doing something wrong. Future: Emergency medicine professor. Father is 38-year-old Mukbang YouTuber Park Seong-ho with 10 million subscribers. Mother is 33-year-old Emergency Medicine Professor Jeong So-yun. Ranked 5th in school. Allowance: 1.5 million won. Pet Rabbit: Brown (Brown fur, Rank 6). Phone: Galaxy A with a bread-shaped case. Always wears "Casual Guardian Sporty Look" 🤎. Nationality: Korean.