Ginrou

Ginrou is cowardly, selfish, vain, excitable, and highly susceptible to promises of personal reward. He frequently searches for loopholes that will let him avoid work or danger while still receiving the benefits of success.

That behavior contrasts sharply with Kinrou's rigid sense of duty, making the brothers natural comedic opposites. Ginrou routinely mocks rules until he sees an opportunity to exploit them, while Kinrou obeys them even when doing so causes problems.

Beneath the cowardice, Ginrou is capable of genuine bravery. His courage usually appears only after fear, complaining, and attempts to escape, but he has repeatedly entered dangerous situations when his friends' lives depend on it.

Ginrou is a trained village guard and spear fighter, though he is less disciplined and physically imposing than Kinrou. His silver-tipped spear is his characteristic weapon.

He has sufficient athletic ability to participate in the Grand Bout and fight other trained villagers, but fear frequently prevents him from performing at his best.

Ginrou's most useful trait is sometimes simple willingness to act despite terror. During dangerous scientific expeditions, he does not possess Senku's knowledge or Kohaku's overwhelming physical ability, yet he can still complete tasks requiring nerve and improvisation.

He is also surprisingly effective at deception when sufficiently motivated, especially when a plan involves disguise or exploiting an opponent's assumptions.

Ginrou and Kinrou initially guard the bridge leading into Ishigami Village, restricting Senku's access because outsiders are forbidden from entering. Senku gradually wins them over through ramen, scientific demonstrations, and the promise of improved weapons.

The search for sulfuric acid becomes Ginrou's first major test. The substance is necessary to produce antibiotics for Ruri, but collecting it requires entering an area where toxic hydrogen sulfide can kill anyone whose protective equipment fails.

Ginrou nearly abandons the expedition out of fear but ultimately helps Chrome and Senku secure the material.

During the Grand Bout, Ginrou enters partly because winning the position of chief would give him access to Ruri and political privileges. His ambitions are repeatedly undercut by his cowardice and the reactions of the village women.

On Treasure Island, Ginrou becomes part of the infiltration operation and is disguised as a woman to enter the inner palace. Despite spending much of the mission terrified, he uncovers critical information about Ibara's plans and eventually risks himself trying to warn the others.

Kinrou is Ginrou's older brother, fellow guard, and constant counterpart. Kinrou's seriousness repeatedly clashes with Ginrou's laziness, but the brothers genuinely care for one another.

Senku Ishigami gradually wins Ginrou's cooperation and turns him from a suspicious village guard into a member of the Kingdom of Science.

Chrome shares several dangerous missions with Ginrou, including the sulfuric-acid expedition.

Kohaku is a fellow village fighter whose strength far exceeds Ginrou's.

Suika belongs to the same early Kingdom of Science group and often sees through Ginrou's selfish schemes.

Matsukaze later mistakes Ginrou for someone connected to his former master and becomes unusually devoted to protecting him.