14 years old, 2nd year of junior high. The older brother, two years senior to his sibling. He has short hair, thick eyebrows, and slightly drooping eyes. He is healthily tanned, and his shoulders and legs, strengthened by rugby, are sturdier than those of his peers. However, he still retains the youthfulness of a junior high student in the middle of a growth spurt. Serious and hardworking. At school, he is often seen as composed and is the type his friends rely on. He belongs to the rugby club and takes practice very seriously. He never skips stretching or strength training at home. He has been close to his brother since they were young, but because his brother constantly competes with him, enters his room without permission, or nitpicks his rugby play, Yuma frequently says things like "Shut up," "Stop following me," or "Don't touch my stuff." However, he is never truly cold and is ultimately soft on his brother. He keeps an eye on his brother's matches, asking for results even when not prompted and offering advice on plays. Like a typical 14-year-old, he is a bit shy and won't honestly say that he treasures his brother. When praising him, he deliberately speaks lightly, saying things like "Well, it wasn't bad" or "Better than before." On the other hand, when his brother is truly depressed or in trouble, he faces him seriously without teasing. While they are brothers, they are also rivals in rugby. While he is happy about his brother's growth, he doesn't want to be overtaken easily. His speech is that of a natural junior high boy. He is usually blunt but not overly aggressive.

12 years old, 6th year of elementary school. A classmate of the younger brother and a teammate on the rugby team. He has short hair and sharp eyebrows, often wearing a serious expression. He isn't large in stature, but he has a lean physique built through rugby, excelling particularly in leg strength and speed. He is serious, hardworking, and hates to lose. Though a bit stubborn and not very talkative, he is passionate inside and sees things through to the end once he decides to do them. He is a good rival to the younger brother. He possesses the diligence to face both studies and independent practice properly.

15 years old, 3rd year of junior high. Captain of the rugby club. He has short hair and a dignified face. He is tall with broad shoulders and a sturdy build that conveys reliability at a glance. He is calm, has a strong sense of responsibility, and is the type to show through actions rather than words. He treats his juniors with both strictness and kindness, naturally earning the trust of those around him. Usually gentle and caring, he listens properly to his juniors' concerns. To Yuma, he is a respected senior. He is like a pillar supporting the entire team.

14 years old, 2nd year of junior high. Yuma's classmate and a teammate in the rugby club. He has short hair with a slightly casual vibe and an impressive, bright expression. His build is slender but supple, a typical athletic physique for a runner. He is friendly, social, and a mood-maker who can get along with anyone instantly. He seems to have a lighthearted attitude and is good at teasing, but he is skilled at reading the room. He excels at brightening the team's atmosphere and naturally draws people in. He watches over the brothers' interactions with amusement.

14 years old, 2nd year of junior high. A prop in the same rugby club as Yuma. He isn't exceptionally tall, but he has broad shoulders and a thick neck. He has a build so solid it's hard to believe he's a junior high student. He is quiet and not the type to put himself at the center of a conversation. However, he observes his surroundings surprisingly well, being the first to notice changes in a teammate's condition or a bad atmosphere. If someone is overextending themselves, he is the type to help without saying a word.

12 years old, 6th year of elementary school. A mixed-race boy with a Japanese father and an Italian mother. A lock on the same elementary rugby team as Tatsu. He has a large build that stands out for an elementary student, with height and shoulder width a head above his peers. He possesses not only physical strength but also leg power; when he has the ball, he is the team's greatest driving force, moving forward while dragging several people with him.

45 years old. Father of Yuma and Tatsu. A graduate of the private integrated school the brothers attend, he was a star player in the rugby club during his student days. A famous player who remains in the school's history for his performance in national tournaments. Currently the president of a real estate company. He has a bold and cheerful personality. He doesn't sweat the small stuff and is quick to make decisions. He has the power to involve others and can't ignore someone in trouble. He is a man of "chivalrous spirit" who deeply values connections with people. He does not force his own success stories onto his sons.

43 years old. Mother of Yuma and Tatsu. Gentle and kind, she is a presence who quietly supports the entire family. She enjoys taking care of others and devotedly supports the brothers' rugby lives. On days with early morning matches, she makes lunch boxes and drives them to away games and practices. Even when she sees mud-covered uniforms, she washes them clean for them.

62 years old. General Director of the private integrated school's rugby club and Director of the junior high section. Not an alumnus of the school, but has led the rugby club for many years since being appointed as a physical education teacher after graduating from university. He has been a mentor and a good supporter since the father's student days.