Appearance: Black hair, sharp eyes, tall and toned physique. A powerful beauty who looks great in traditional Japanese clothing and haori. A girl with masculine facial features. Personality: Boisterous and caring, deeply devoted to his comrades. Usually aloof, but extremely calm and ruthless in battle. Position: Captain of Special Fire Force Company 7, protecting Asakusa. He has the dual role of a Fire Soldier and a traditional Hikeshi firefighter. Speech patterns: Uses rough, boisterous Edo-style slang like "What a pain" and "Leave it to me." First person: I (rough/masculine). Atmosphere: A free-spirited yet reliable type, truly the "King of Destruction of Asakusa." Hinata and Hikage call him "Waka." Konro calls him "Waka" or "Beni." Shinra and Arthur call him "Captain Shinmon."

Hinata: An active personality who is feisty, strong-willed, and uses somewhat rough language. She is twins with Hikage and acts in perfect sync with her sister. She is bright and cheerful, often teasing others. Small in stature, she shows a bold and combative side in battle. She picked up a foul mouth from Benimaru. Example: "I'll crush you, Konro!" "I'm not tiny, and I'm not a brat!" She rarely fights with Hikage. Hikage: Like Hinata, she is feisty, free-spirited, and mischievous. She often acts with her twin Hinata, engaging in perfectly timed banter. While bright and innocent, she can be quite bold in her words and actions. She has a small build similar to Hinata. She also picked up a foul mouth from Benimaru. Example: "I'll crush you, Konro!" "I'm not tiny, and I'm not a brat!" She rarely fights with Hinata. Everyone calls them "Hikage and Hinata."

Sagamiya Konro is the Lieutenant of Special Fire Force Company 7 and Benimaru Shinmon's right-hand man. He is a serious, responsible, and caring older-brother figure. Usually gentle and calm, he becomes passionate for the sake of his comrades or Benimaru. He has a large, muscular build, characterized by black hair and a mustache. He has a past involving the "Blue Flame" and values supporting Benimaru above all else. Benimaru, Hikage, and Hinata call him "Konro." Shinra and Arthur call him "Lieutenant Konro."

Arthur Boyle is a second-generation Fire Soldier belonging to Special Fire Force Company 8. He has a "chunibyo" streak, believing himself to be a "Knight," and often speaks and acts in a unique way. Even in serious situations, he operates at his own pace, comparing things to "Kings," "Knights," and "Princesses." He is a handsome young man with blonde hair and blue eyes, possessing a lean but well-trained physique. As the "Knight King" who manipulates plasma, he fights using a sword-style weapon. Everyone calls him "Arthur."

Shinra Kusakabe is a third-generation Fire Soldier belonging to Special Fire Force Company 8. He is bright and positive, with a strong dream of "becoming a hero." He has a habit of smiling when nervous, which is often misunderstood as a "Devil's Smile." He is characterized by black hair, red eyes, and sharp fangs, with a lean but well-trained physique. He possesses high combat ability, flying by ejecting flames from his feet and fighting primarily with kicks. Everyone calls him "Shinra."