A mother boar raised Inosuke Hashibira ever since he was young and thrown to safety into water by his mother shortly before she died. Whilst he did live in the mountains by himself he still managed to learn how to talk by learning from other humans. These humans were Takaharu and his elderly grandfather.
Growing up, Inosuke survived fighting vicious demons in the mountains. Although The Beast Breathing is a branched-out version of wind breathing, Inosuke self-taught this technique without anyone's supervision.
Kyojuro Rengoku
Like Tanjiro and Zenitsu, Inosuke is immediately taken with the strong and magnanimous Kyojuro, looking up to him as a mentor and leader after they meet on the Infinity Train.
Since this Breathing Style is personally created and self-taught by Inosuke Hashibira after living in the mountains and fighting for survival, it can be assumed that it can only be utilized by someone with dual Nichirin katanas and an extremely acute sense of touch.
Inosuke was raised by boars for most of his life before the Final Selection. It was revealed later that he was born into a family with an abusive father and escaped from his father with his mother. Inosuke as child with his mother.
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.
Overall Abilities: Inosuke is a very skilled and talented swordsman as he was able to learn Total Concentration Breathing on his own and develop his very own Breathing Style known as Beast Breathing based on his own instincts and upbringing in the mountains by wild boars and passed Final Selection to become a Demon ...
Inosuke Hashibira, a half-demon among demon slayers.
Inosuke Hashibira (嘴平 伊之助) is one of the two tritagonists (alongside Zenitsu Agatsuma) of the 2016-2020 fantasy horror manga/anime series Demon Slayer: Kimetsu no Yaiba and its 2020 stage play.
Master Swordsmith: Hotaru is a skilled swordsmith, able to forge the Nichirin Sword and repaired it multiple times each time it broke against the Lower and Upper Ranks.
There are six forms, but Zenitsu could only learn the first form said to be the basis for the others yet he honed it to where he could fight against several strong demons. He later created a seventh form and defeated his former senior who had become the Upper Rank Six of the Twelve Kizuki.
After killing Inosuke's mother, Doma assumed that Inosuke had perished from the fall and returned to his lair. Inosuke was carried downstream and was eventually taken in by a wild boar, who raised him as its own until it passed away.
In her final moments, she apologized to Inosuke for failing to protect him and tosses him into the river as an attempt to save his life. She was ultimately killed and eaten by Doma, who claimed to have devoured her to the bone.
Aoba Hashibira (嘴 (はし) 平 (びら) 青 (あお) 葉 (ば) , Hashibira Aoba?) is the great-grandson of Inosuke Hashibira and Aoi Kanzaki. He is a well known botanist involved in researching the Blue Spider Lily.
After the final battle
It is confirmed in the Volume 23 extras that Inosuke and Aoi did eventually end up together and that they have two great-grandsons, one of which is Aoba.
Inosuke is probably the closest to Zenitsu in terms of power, considering they're both new Demon Slayer recruits and they're both less skilled than Tanjiro. If they ever were to face off, however, it's likely Inosuke would win.
I'd say Inosuke has a 65% win rate on ZENITSU maybe lower, and tanjiro has a 85% win rate. Tanjiro is a very talented Demon Slayer, enough to be considered a prodigy at this rate.
Inosuke tells Tanjirou his name and to never forgot that while calling him Mr. Forehead.
A mother boar raised Inosuke Hashibira ever since he was young and thrown to safety into water by his mother shortly before she died. Whilst he did live in the mountains by himself he still managed to learn how to talk by learning from other humans. These humans were Takaharu and his elderly grandfather.
Sakonji Urokodaki is one of the playable characters in Demon Slayer: The Hinokami Chronicles. A former member of the Demon Slayer Corps, Urokodaki is Tanjiro's master and he was also the master of Sabito and Makomo before they died.
Inosuke dreamed that he was the leader in the team to defeat the train, being Nezuko, Tanjiro and Zenitsu his subordinates. He went after Nezuko and gave her some acorns so she could also be part of the attack.
Fourth Fang ( 肆 し ノ 牙 きば , Shi no kiba?) - The user performs four forward slashes in quick succession, striking the target three times before unleashing a powerful fourth slash, launching them away.
Jigoro Kuwajima ( 桑 くわ 島 じま 慈 じ 悟 ご 郎 ろう , Kuwajima Jigorō?) is the man who trained Zenitsu Agatsuma and Kaigaku.
Inosuke operates with two blades that are a cool indigo-grey in color, in response to Inosuke's beastly nature. Breath of the Beast is certainly appropriate for Inosuke and it meshes with the sleek nature of indigo-grey.
After Muzan was defeated, all the demons he created also perished immediately, so there was no point of a Demon Slayer corps anymore. As a result, Zenitsu did not get to become a Hashira even after becoming strong enough to bie one.