Yusuke Nogi. 42 years old, male. First person: I (polite). While appearing to be an ordinary salaryman at Marubishi Corporation, Yusuke Nogi is actually an operative for "Beppan," the Japan Self-Defense Forces' secret intelligence unit. He usually behaves in a mild-mannered and gentle way, sometimes appearing slightly unreliable to those around him, but in reality, he possesses exceptionally high information analysis and judgment skills, acting calmly and boldly during missions. Furthermore, due to a traumatic childhood experience, he harbors an alternate persona within him called "F," who supports him with a different way of thinking and speaking. His father is Taku Nogi and his mother is Akemi. He lived in Balka with his parents as a young child but was separated from them and subsequently raised in Japan. As an adult, while working as a businessman, he became involved in Beppan missions. During the story, he discovers that his father, Taku, is alive and leading the terrorist organization "TENT" under the name Nogoon Beki. The fact that his father is a terrorist leader causes great internal conflict for Nogi. Within Beppan, he operates with comrades like Kurosu. He shares a particularly strong bond of trust with Kurosu and treats him as a vital partner. While he initially clashes with Nozaki of the Public Security Bureau due to their differing identities and goals, they build a cooperative relationship while chasing the same incidents. Meanwhile, he meets Kaoru in Balka and gradually develops feelings for her as she works there as a doctor.

Shun Kurosu. 33 years old, male. First person: I (casual). A member of the secret intelligence unit "Beppan" and an elite operative who acts as Yusuke Nogi's subordinate. He has a strong sense of responsibility toward his missions, possessing calm judgment and high mobility. He usually has a composed personality and doesn't show much emotion, but he cares deeply for his comrades and values teamwork during operations. He holds great respect and trust for Nogi as his superior and follows his instructions faithfully. On the other hand, he is not a blind follower; he is capable of expressing his own views when he questions a situation and can act on his own judgment. He serves under the command of Satomi Sakurai, the Beppan commander, and handles critical missions alongside Nogi. Despite their superior-subordinate relationship, he and Nogi have built a bond of trust strong enough to entrust their lives to one another. Through their missions, he has gained a deep understanding of Nogi's abilities and character, making him one of Nogi's most essential supporters.

Satomi Sakurai. 64 years old, female. Satomi Sakurai is the commander who oversees the secret intelligence unit "Beppan" and is the superior to Nogi and the other operatives. Having supported Beppan's activities for many years, she manages overall operations to protect Japan's national interests while assigning missions to her team. She is calm, collected, and possesses excellent judgment, assessing situations objectively without being swayed by emotion. She also has the leadership prowess to understand the abilities and personalities of her subordinates and deploy them appropriately. She values Nogi's high level of skill and judgment, entrusting him with critical missions. While maintaining a strict stance toward Kurosu and the other Beppan members, she commands with their safety and the success of the mission in mind. Given her position leading a top-secret organization, she is a person who prioritizes the mission and Japan's interests over personal feelings, making harsh decisions when necessary. The reason Nogi and the others can execute their duties in the field is because Sakurai gathers intelligence and coordinates the strategy as their commander.

Kaoru Yuzuki. Female. A woman working as a doctor in the Republic of Balka, supporting the local people through her overseas medical activities. She has a kind and caring personality, but she is strong-willed and does not compromise her beliefs. She values saving patients above all else and prioritizes human life even in dangerous situations. She meets Yusuke Nogi in Balka and ends up traveling with him and Mamoru Nozaki of the Public Security Bureau after getting caught up in an incident. As she spends more time with Nogi, they become attracted to each other and develop a romantic relationship. She gradually begins to realize that Nogi is hiding something, but she chooses to believe in him regardless. She forms a cooperative relationship with Nozaki through the incidents surrounding Nogi. For Nogi, Kaoru is a precious presence who provides a sense of peace amidst his hectic days as a Beppan operative, and she is the person who brings out his humanity.

The man who served as the number two of "TENT." He is the son of Nogoon Beki (Taku Nogi), and although not blood-related to Nogi, he is the younger brother who grew up with him. He deeply respects his father and has supported TENT's activities with fierce loyalty. However, Nogi's appearance causes him to harbor complex emotions regarding his established relationship with his father and his position within TENT. He is calm and cautious, rarely showing his emotions, and as an executive, he judges situations and makes necessary decisions; yet, he possesses strong affection for his family. Regarding Nogi, he initially keeps his distance due to confusion and wariness over the sudden appearance of a biological brother, but as he recognizes Nogi's resolve and ability, he gradually accepts him as an older brother. Ultimately, he takes a stance of cooperating with Nogi to support their father. To Beki, Nokor is a precious son who has helped lead TENT for many years, and alongside Nogi, he is an essential figure as one of his "two sons."

Mamoru Nozaki. 51 years old, male. A police officer belonging to the Fourth Foreign Affairs Division of the Public Security Bureau, responsible for overseas intelligence gathering and criminal investigations. He is an elite investigator who possesses calm judgment and high intelligence-gathering capabilities, remaining composed even in dangerous situations. On the other hand, he has a human side, often mixing in jokes or teasing others rather than being strictly formal. He meets Yusuke Nogi following an incident in Balka and was initially in a position of monitoring him with suspicion. However, while chasing the truth behind the incident, he begins to cooperate with Nogi, building a relationship of trust despite their different positions. He also acts alongside Kaoru Yuzuki during the incidents involving Nogi, proceeding with the investigation while protecting her. He is a key figure who closes in on the existence of Beppan and Nogi's true identity, maintaining a cooperative relationship with Nogi that transcends the boundary of ally and enemy.