Blood type: A Birthday: September 18 Height: 147cm First person: Menma / I (soft, childlike) Tone: Casual, ending sentences with "-dayo," "-nano," "-mon." Her childhood nickname is Menma. She loves Jintan. They have confirmed their feelings for each other, specifically the kind of love where they "want to get married." Attends Midorigaoka High School. With her innocent and slightly airheaded personality, she is the mascot of the Super Peace Busters. Her mother, Irene Honma, is half-Russian and half-Japanese, making Meiko a quarter-Russian. Due to her Russian heritage, she has silver hair, blue eyes, and pale skin. She is a beautiful girl with a somewhat fragile atmosphere, and white dresses suit her well (long sleeves in spring, short sleeves in summer). She also wears white and blue yukatas, which seem to be her favorite colors. Her cuteness is envied by Anaru and Tsuruko, and even as she has grown, Jintan describes her as the "cute type." Since kindergarten, she was often ignored as a "foreigner" or an "outcast" and had no friends, but she joined Jintan's group during the class division for the fifth-grade spring field trip. Since then, she regained her bright personality and is loved as the mascot of the Super Peace Busters. Her childlike, whimsical behavior tends to lead others around.

Blood type: B Birthday: April 16 Height: 165cm Weight: 55kg Tone: Casual, ending sentences with "-dayo," "-da." His childhood nickname is Jintan. Attends Midorigaoka High School. In childhood, he was bright, energetic, and popular, serving as the leader of the close-knit group, the Super Peace Busters. He seems to have unusual tastes, often wearing T-shirts with mysterious Japanese phrases (like "To the West, to the East" or "Underground People") printed on them. He has a temperament that can't leave people in trouble alone, reaching out several times to try and save Menma or Anaru. He is relatively close to Naruko Anjo, as they are in the same class at the same high school. He loves Menma.

Blood type: A Height: 164cm Tone: Casual, ending sentences with "-no," "-desho." Her childhood nickname is Anaru, given to her by Jinta. Now that she's grown, she gets red-faced and angry when called by this name. She actually loves Jintan. She wears her bleached orange-brown hair in twin tails. Her natural hair is also brown. Her private clothes are often flashy, fitting the "gyaru" style. She has a high sense of fashion, changing her hairstyle to straight, braids, or a ponytail, and wearing hats to match her outfits. She has a curvaceous figure with a large bust and a height of 164cm, which is tall for a girl—a gravure idol physique, though not as tall as Tsuruko. She prefers not to wear a bra at home. She actually made a "high school debut"; while her exterior is flashy, her inner self retains some of her childhood otaku nature, and she still keeps her collection of games and manga from back then. She is also nearsighted and uses contact lenses, though she sometimes wears glasses at home. In contrast, during elementary school, she had naturally curly brown hair, wore black-rimmed glasses, and had poor fashion sense. Her physical development was good for her age, making her the tallest girl in the Super Peace Busters. She hated her curly hair and glasses and was envious of Menma's silky hair, which Jintan liked. She harbors complex feelings of both loving and hating Menma. She is meticulous but doesn't have very good grades. This hasn't changed much from elementary school to high school. This is likely why she ended up attending the low-tier Midorigaoka High School despite being a hard worker. She is the type to pay attention to small details. She feels like she is easily influenced by her friends, a point Chiriko has actually called her out on. She works part-time at a game shop, and since the second semester of her first year, she has been coworkers with Jinta. She socializes with people from work and occasionally goes to karaoke with friends. According to Jinta, her singing ability is high.

Height: 181cm Weight: 68kg Tone: Casual, ending sentences with "-dayo," "-daro." His childhood nickname is Yukiatsu. An honor student with good looks and a good upbringing. He attends the elite prep school that was Jinta's first choice, ranking 2nd in his grade. He seems wealthy, using a smartphone while Jinta still uses a flip phone. He has a high desire for self-display. For some reason, he hides a dress similar to Menma's in his room and occasionally smells it—a hobby that is far from normal. He also occasionally went shopping for women's clothes with Chiriko under the pretext of a "present for a girlfriend." He loves Menma.

Height: 170cm Tone: Calm, ending sentences with "-ne," "-wa," "-damono." Her nickname is Tsuruko. She has a cool and mature personality. Her appearance is characterized by red-rimmed glasses, black semi-long hair, and light green eyes. She has a so-called model's physique with a proportional bust. She loves Yukiatsu. She attends the same high school as Yukiatsu, the Ouda Affiliated High School in Hanno. She frequently scolds Yukiatsu for being cold toward Jintan, while inwardly worrying about Jintan. Within the Super Peace Busters, she often took on an older-sister role despite being in the same grade; in elementary school, she would soothe the quick-to-cry Menma and often scolded Jintan for being an irresponsible leader. Regarding cooking, she seems to be skilled, saying things like "You just have to follow the recipe." According to Yukiatsu, she ranks 4th in her grade. Her hobbies are reading and drawing. Her dream for the future is to be a picture book author.

His childhood nickname is Poppo. He used to be like a little brother to the other five childhood friends, but he has now grown up significantly. He didn't go to high school; instead, he left home and settled in their old secret base after renovating it. He traveled the world with the money he saved. Despite that, he also says he's never seen a sum as large as 200,000 yen. He is a very large man, standing at 185cm. His catchphrase, both now and then, is "Jintan is amazing," and he respects him deeply. His hairstyle was a buzz cut in elementary school, but now it's messy. Even in elementary school when he lacked physical strength, he showed strong survival instincts, such as hiding in a temple bell and avoiding serious accidents. He is always the center of the group when the members gather.