Hairo

Hairo, also known as the "Gun Demon" is the primary antagonist of Kyojuro Rengoku's Gaiden of Demon Slayer: Kimetsu no Yaiba. He is a Demon affiliated with the Twelve Kizuki, having formerly held the position of Lower Rank Two (の).

Appearance
Hairo appears as a young man with an athletic build. He has incredibly spiky black hair with two chin-length bangs framing his face. As a member of the Twelve Kizuki, he has the kanji for Lower and Two etched on his left eye.

He wears an western light suit with a black buckled belt with saggy pants and black boots. Over this, he wears a black cloak similar in appearance to a cape with protruding collars. Finally he wears a white sailor hat with a wolf emblem on its front center.

Personality
Hairo appears to have immense anger management issues, coming to the point of him being "suicidal": shooting himself in the head to contain it. The main cause is presumed due to mistreatment from his human life when being a member of the Shinsengumi. Despite his near constant anger, he has shown humbleness, seen when he venerated Kyojuro Rengoku's swordsmanship before his death.

History
Not much is known about Hairo, but it is known that at some point of his life, he mastered the art of Bushidō but was harassed by a group of marksman who insulted his swordsmanship. At some point when he became a Demon, he was nearly killed by Shinjuro Rengoku, but was either spared or escaped, and gained strength, becoming Lower Rank Two.

Abilities
Overall Abilities: Due to Hairo being Lower Rank Two of the Twelve Kizuki, he is exceptionally more powerful than any average demon, his power exceeding that of the Lower Ranks Kamanue, Rui, Mukago, Wakuraba, and even rivaling Rokuro. However, due to his rank, his power should not even compare to the power of Lower Rank One, Enmu. He was able to stand his ground against Kyojuro Rengoku who was a Kinoe at the time, which is the highest non-Hashira rank of the Demon Slayer Corps.

Enhanced Regeneration: As a member of the Twelve Kizuki, Hairo possesses great regenerative abilities, shown when he re-grew his entire upper body in a matter of seconds after having it completely destroyed in an explosion.

Skilled Torturer: As stated by Hairo himself, when he was human, he was extremely experienced in torturing people using a variety of methods. Hairo instinctively knew when someone was about to hit their breaking point as long as they are alive. He even has the mindset of someone who enjoys inflicting pain and suffering on others, shown when he expressed joy over wanting to torture Mitsuri Kanroji to indirectly affect Kyojuro Rengoku.

Blood Demon Art
Umbrakinesis: Hairo's Blood Demon Art allows him to create and manipulate shadows with special properties and characteristics from his flesh and blood. His shadows have unique shapes and designs on them, ranging from white triangular patterns to eyes. These shadows contain a suction effect with not only absorbs damage from physical attacks, but also makes it extremely difficult to escape when in contact with them. Furthermore, the shadows also have a special property that seemingly gives even a dimensional pocket to store countless items and he can conjure these items from anywhere his shadows occupy. Hairo usually opts to shape his shadows or the shadows of objects or people into wolves to increase his attack potency and striking range. Otherwise, he would turn parts of his body into his Blood Demon Art to nullify attacks and trap his enemies.
 * Artillery Manipulation: As Hairo's shadows contain a countless number of weapons, ranging from pistols to bolt-rifles to shotguns and sub-machine guns, even containing a rotatory mini-gun, molotovs, dynamite and other explosives, and also a large katana. He can command these to fire at will, whether it be from his own body or from shadows he has sent out in the environment as traps, or even from the shadow wolves of his Blood Demon Art. However, these guns are real and not mystical, having a significant but limited amount of ammunition. Thus if he runs out of bullets, the guns become useless.

Fighting Style
Expert Marksman: With the nearly infinite supply of weapons at his disposal, Hairo has displayed the ability to be extremely proficient in his plethora of firearms and ranged weapons.

Expert Swordsman: After depleting his supply of firearms, Hairo switches his combat stance and uses his Bushidō sword technique. His sword skill can even match the likes of Kyojuro, albeit that was when his skill wasn't as polished as when he became a Hashira.

Techniques
Plunder Cavity These techniques involve shaping his shadows into wolf-like entities and using his countless supply of weapons to attack:
 * -|Techniques=
 * Shadow Wolf - Hairo creates multiple shadowy wolves from his blood that emanate from his cloak, these wolves have the same suction effect as his regular shadows and thus can absorb a plethora of physical attacks and make them exceptionally hard to kill. These wolves can also conjure guns and other weapons.
 * Ravaged War Formation Wolf - With his own blood he gathers all his shadows to him and cloaks himself in them, which transforms him into a large shadowy wolf standing on its hind legs.
 * -|Demonstrations=

Equipment
Weapons Arsenal: Hairo has a huge arsenal of weapons, both melee and ranged weapons used for combat purposes found around that time period. Ranged weapons include pistols, bolt-rifles, hotguns, sub-machine guns, even containing a rotatory mini-gun, molotovs, dynamite and other explosivesThe only close ranged weapon is a standard katana.

Trivia

 * Hairo would usually collect Demon Slayers's Nichirin Blades as trophies for him killing them.
 * Judging from his flashbacks, Hairo was probably a part of the Shinsengumi, a special police force organized by the Bakufu (military government) during Japan's Bakumatsu period (late Tokugawa shogunate) in 1863.

Quotes

 * (To Mitsuri Kanroji) "I'll take you to the limit of human pain. And deal with you in a way you'll never forget for the rest of your life. Your life will be consumed for my revenge. And it's your fault. You must take responsibility for joining the Demon Slayers. Pathetic. Just pathetic. Nobody will know you, nobody will accept you. All you Demon Slayers will encounter nothing but pathetic deaths."
 * (To himself) "My wounds may have healed, but the fear and rage from that day haven't quelled since. I can't bear living my life in fear of this man! I'll die of pure indignation!"
 * (To himself) "Impossible. I showered him with so many bullets and rained explosives onto him multiple times. How can I not beat this guy!? Why is he coming at me with a mere sword? How can this human stand up against me? Is this man... is this man really the man I met that day?"
 * (To Kyojuro Rengoku) "...Nice swordsmanship."