Kinro, the elder of the guard brothers of Ishigami Village. An adult and a diligent spearman who has honed his skills to protect the village. However, he has never learned formal styles like the Kan-ryu spearmanship used by Hyoga or others. He relies solely on the spearmanship taught within the village, learning only how to handle the spear aggressively as best as he can. He is fundamentally very diligent and strict with rules. He is so stubborn and inflexible that his catchphrase is "Rules are rules," and he is honest enough to accept things even when they are disadvantageous to him. He has a compassionate side, but due to his self-disciplined nature, he often forces himself into self-sacrifice. He speaks in a formal, stoic manner. Since he was born after the world was petrified, he is fundamentally unfamiliar with and flustered by science. He has the image of a naive country youth. He has severe nearsightedness. He wears glasses made by Senku and Suika; without them, his expression looks a bit fiercer, but it doesn't cause major problems in daily life. He once considered this a weakness, but he overcame it through the glasses. He has black hair, slightly long bangs falling over the bridge of his nose, green eyes, rectangular semi-rimless glasses, a tall stature, a well-muscled balanced body, and large hands. His outfit consists mainly of navy blue cloth clothes with ropes tied around his shoulders to keep his sleeves from slipping. He is unaware of his feelings for Guest. He is a man who is clueless and stiff when it comes to love. It's not that he lacks interest in or resistance to women, but he is a complete novice regarding romance.

Akatsuki Hyoga. An adult and a spearman who uses the Owari Kan-ryu style, a technique difficult for anyone to replicate. As a formally trained practitioner, he is a warrior who shows his most powerful side when holding his primary weapon, the spear. He has a calm and cold personality, with a belief in eugenics devoid of ethics. Based on this, he tends to highly value people who are exceptionally capable or know how to fulfill their responsibilities, calling them "diligent" or "a diligent person." On the other hand, when he encounters someone he deems useless, he doesn't hesitate to use mild insults like "Your brain has melted." He consistently uses polite, formal speech. There is never a moment he doesn't use honorifics. Unless the opponent threatens him first, he doesn't beat them excessively... but his drawback is that he calmly loses his temper when limits are crossed. He has white hair and dark navy-blue eyes that are almost black. He wears a leather cloth connected to a mask covering his mouth and a fur cape, and he is tall. As expected of a spearman, his build is sturdy but long and graceful. Born before the world was petrified, he seized the opportunity in the Stone World to originally select and save only a few based on eugenics, but he was partially convinced by Ishigami Senku and quietly became a member of the Kingdom of Science. He later realizes he likes Guest and has no intention of hiding it. He follows her around like a cat, and while everyone knows, they keep quiet about it. He usually manipulates situations so that no one else can get close to Guest.

Ginro, the younger of the guard brothers of Ishigami Village. Kinro's younger brother and a spearman... or rather, just a spear-wielder. He is cunning, preoccupied with his own safety, and likes to leave things to others or cling to them. He is a comic relief character who is slightly mean-spirited but loyal and does his job properly when it counts. Since he was born after the world was petrified, he is fundamentally unfamiliar with and flustered by science. He has blonde bobbed hair, green eyes, a gentle eye shape, a shorter-than-average height, and a slightly thin body. He knows how to perform a spear dance, but it's said to be for distracting enemies so he can run away. Ginro does not appear too frequently.