Goromaru is a samurai who appears in the Onimusha anime series as a member of the group sent to assist the legendary swordsman Musashi Miyamoto. He is one of the more skilled warriors among the men enlisted for the mission to confront the traitor Iemon.

In terms of personality, Goromaru comes across as approachable and somewhat down-to-earth, showing both courage and moments of vulnerability. He is knowledgeable about famous warriors and does not hesitate to share stories about Musashi's legendary battles, indicating a degree of admiration and respect for great swordsmen. However, he also shows a practical side, such as doubting the accuracy of a companion's fortune-telling and noting that such predictions are only correct half the time. When faced with terrifying zombie-like villagers, Goromaru openly shows fear but is able to overcome it with encouragement from his comrades, demonstrating that he is not fearless but possesses the resolve to fight despite his fear.

Goromaru's primary motivation is tied to his duty as a samurai. He is part of a covert mission to stop Iemon, who betrayed his lord after discovering a gold mine in a village. Despite the danger, Goromaru chooses to remain with Musashi even after the group learns they will be facing demons, showing a strong sense of loyalty and commitment to the mission.

Throughout the story, Goromaru serves as a supporting member of Musashi's team. He travels with the group, participates in battles, and provides assistance to his allies. His role becomes particularly notable during the attack by the transformed villagers, where he uses his unique skills to protect the group. He also takes part in investigating the abandoned village, searching for clues about what happened to the inhabitants.

Goromaru has several key relationships within the group. He interacts regularly with his fellow samurai, including Sahei, Heikuro, and the monk Kaizen. He shares information with Kaizen about Musashi's reputation and engages in conversation with Heikuro about the nature of their mission and the traitors among them. His most distinctive relationship, however, is with his two pet falcons named Taromaru and Jiromaru. These birds are not merely companions but active participants in battle, attacking enemies on Goromaru's command.

In terms of character development, Goromaru shows growth from a samurai who is initially afraid of monsters into a warrior who can stand his ground against them. When the zombie villagers attack, he struggles with fear, but with Heikuro's help, he manages to kill one of the creatures. He then summons his falcons to aid in the fight, demonstrating tactical thinking under pressure. When Taromaru is hit and falls, Goromaru rushes to save his bird, showing deep loyalty to his animal companions and risking his own safety for theirs.

Goromaru's most notable abilities include his skill as a swordsman, as he is described as one of the more skilled men on the mission. However, his most unique and remarkable ability is his partnership with his two falcons. Taromaru and Jiromaru are trained to attack enemies, and they prove highly effective at beheading the zombie-like monsters that the group encounters. This falconry ability sets him apart from the other samurai and provides a distinct tactical advantage in battle.