Benimaru Shinmon is a hybrid Second and Third Generation, as well as the Captain of Special Fire Force Company 7. Benimaru is regarded as the strongest Fire Officer in the Special Fire Force. He is known as "Asakusa's King of Destruction" because of the devastating power that he is capable of unleashing. He is also an extremely skilled hand-to-hand combatant, as shown when he easily outmaneuvered and overpowered the combined might of Maki Oze, Shinra Kusakabe, Tamaki Kotatsu, Arthur Boyle, and Takehisa Hinawa. He possesses the rare trait of being a Second and Third Generation, which ultimately allows him to ignite his own flames willingly, and also control flames from an external source. He can use his brigade's matoi as a pole to fly to long-distance areas, and by using his Second Generation ability, can control the flames of other ignited matoi and direct them to a certain place. He can control the direction and speed of bullets in the same fashion as Takehisa. He is also capable of unleashing an immensely powerful blast that resembles a crimson-coloured moon, which is strong enough to kill a Demon Infernal.

Benimaru is a practitioner of the iaido martial arts. Instead of using a sword, he can create a sharp blade of flames, a technique branching from his unique Iai Hand-Sword: First Form fighting style.