Iwao Oguro

Knuckleduster (ナックルダスター) is a vigilante.

Appearance
Knuckleduster is a towering, heavily muscled man. What is visible of his face under his mask reveals heavy stubble and part of a scar along his left cheek. His costume consists of a simple wrap-around mask tied over the top of head, a tight-fitting dark shirt, jeans, boots, a trench coat, and a pair of gloves topped with a pair of brass knuckles, or knuckledusters, from which he derives his name.

Personality
Despite his intimidating appearance, Knuckleduster is actually a very caring and good-hearted individual with a drive to do the right thing. Despite having no government-issued hero license, he still puts on his costume and goes out every night to fight street-level criminals and local gangs to keep his neighborhood safe from crimes most "heroes" won't bother with.

He appears to enjoy a challenge, and becomes very upset or frustrated whenever there are no particularly strong Villains to fight. when a fight is too easy, he quickly becomes depressed. He also prefers to punch first, and ask questions later, as he is willing to beat up people he deems to look suspicious on the slim chance that they may be villains or users of the Trigger drug. His attitude extends that he was willing to attack a defenceless young-appearing woman who had a Hero Provisional licence, and felt little to no guilt or worry about doing so, despite the fact that he could have been registered as a Villain if the misunderstanding continued, showing a more aloof and careless side to his personality.

Despite having no Quirk, he shows no resentment towards people who do, and shows no fear towards Villains who have powerful Quirks. In fact, he seems to enjoy fighting against particularly strong people who have powerful Quirks. This seems to be one of the main joys of his life, as he becomes invigorated whenever he gets to fight a strong opponent. He is even willing to fight against professional Heroes if the situation calls for it. Despite this reckless streak, he does genuinely admire Heroes for the work they do, and it is hinted that he would like to be a Hero himself, despite not having a Quirk, hence his Vigilante work.

Strengths and Abilities
Overall Abilities: Knuckleduster is Quirkless, proven when Shouta Aizawa tried to erase his Quirk only to have no effect on Knuckleduster. Despite being Quirkless, Knuckleduster is incredibly tough in strength and skill as he was able to fight on even terms with Shouta. He was also able to single-handily defeat Stendhal with a single blow.

Hand to Hand Combat: Knuckleduster appears to be skilled in hand-to-hand combat utilizing brass knuckles as his weapon of choice. His skill with his fists was great enough to overcome Chizome's skill with the sword, landing a heavy blow before Chizome could scratch him.

High Durability: Despite being Quirkless, Knuckleduster is very sturdy, standing up even when he receives blows from Villains with physical enhancement Quirks.

Equipment

 * Grappling Hook: He has been seen swinging from buildings with a grappling hook.

Kazuho Haneyama
The two are fellow Vigilantes, but their relationship can be deemed as a rocky one as both tend to bicker with one another on more than one occasion. Kazuho does not not appear to tolerate Knuckleduster's aggressive and violent attitude, especially when it gets out of hand. Despite that, the two are capable of working together during Vigilante missions.

Vigilante - My Hero Academia: Illegals -

 * Knuckleduster vs Stendhal: Win

Trivia

 * His personality also bears a resemblance to Batman, a hero in American comics who is also extremely skilled at hand-to-hand combat that has no real powers.
 * He is also very similar the Wildcat a.k.a Ted Grant, a hero who is known for his aggressive fighting style and personality.