Demon Slayer has shown fans a number of different fighting styles. These fighting styles all stem from types of breathing styles, all of which come from the Sun Breathing, the first breathing style to be created. Many more have been mastered from there, all branching off of each other like a giant tree. Inosuke Hashibira is the creator and only user of beast breathing. Along with his life in the wild, this style has caused Inosuke to develop a unique fighting style.
Inosuke never knew his parents growing this due to his mother being devoured by Doma. In an effort to escape the demon Doma, Kotoha tossed Inosuke into a river in hopes of saving his life. He was later discovered by a family of boars and raised as one of them. Knowing nothing else but the wilds, Inosuke took on the characteristics of the boars, even having a boar mask to cover his face. It's these roots that shape Inosuke's personality and fighting style.
Beast Breathing
Beast Breathing, related to Wind Breathing, is a style developed by Inosuke. This style of breathing focuses on the unpredictability of animals, making the forms and overall fighting unpredictable and in the moment. Something that is crucial to Beast Breathing is utilizing the sense of touch.
Fans may recognize this from when Inosuke scanned the forest when fighting the demon spider family. This spatial awareness means the user of Beast Breathing has a sense of where their enemies are, allowing them to target the enemy.
In Beast Breathing, there are ten known techniques requiring two swords. The two swords mimick the tusks of a boar, causing many of the formations to involve fast-paced attacks, focused on a large amount of damage rather than a clean strike.
These qualities combined make Inosuke's swordsmanship dangerous in close ranges. With two swords and a thirst for blood, Inosuke can feverishly strike his opponents down with little mercy, similar to a boar. Though with no planning or forethought to his attacks, Inosuke's attacks can be deflected easier, after the enemy realizes his sword techniques. Luckily Inosuke has other tricks up his sleeves, except he doesn't wear a shirt.
Fighting Style
Along with Beast Breathing, Inosuke has trained his body to fight differently compared to the other demon slayers. One of them being his incredible flexibility. He shows this to Tanjiro and Zenitsu after escaping the demon house. Without a second thought, Inosuke bends backward, allowing his head to peak out between his legs. He can also dislocate his joints to extend his reach, a site that would probably shock the Demon King himself.
If none of these skills help Inosuke win the fight, his unusual fighting stance will throw his enemy off their game. Since Inosuke bases so much of his like and abilities on boars, it's no surprise that he fights like on as well. Inosuke stays low to the ground when running and fighting, almost like he is running on all fours. This stance allows Inosuke to run faster and surprise his opponents by attacking in an unusual location. When fighting Tanjiro for the first time, Inosuke stays low to the ground, using his arms and legs for attacks. Forcing Tanjiro to fight lower than he is normally used to, giving Inosuke the upper hand.
For Inosuke, fighting like an animal is no problem at all; it's what he'd prefer. This gives him an edge over other demon slayers because his swordsmanship, breathing style, and fighting stance aren't used by anyone else. In cases that none of these work, Inosuke can always take his mask off and surprise his enemy with how beautiful of a face he has.