The One Challenge Tanjiro Will Never Be Able To Complete On Demon Slayer

"Demon Slayer: Kimetsu no Yaiba" is arguably one of the most popular manga and anime series from the past decade. Created by Koyoharu Gotouge, it follows Tanjiro Kamado on his quest to turn his sister, Nezuko, back into a human and defeat Muzan, the demon responsible for slaughtering his family and turning his sister into a demon. 

The series has done extremely well. Its 23rd and final volume was the best-selling manga of the year with over 4 million copies, outselling the equally-popular "Jujutsu Kaisen," according to Anime News Network. A movie entitled "Mugen Train," which covers the manga arc of the same name, was released theatrically in October 2020. Despite the pandemic, it became the second-highest-grossing anime film in U.S. box office history, as reported by Funimation. 

Because of Tanjiro's quest to defeat Muzan, who has eluded the Demon Slayer Corps for years, he must undergo rigorous training to master the Breath techniques and his own Kagura Dance. During his journey, fraught with heartbreak and death, Tanjiro has made friends that train alongside him as he works with the Hashira — the most powerful warriors in the Corps — to become stronger. In this arc, Tanjiro demonstrates his determination and strength, but he can never complete the challenge from the Wind Hashira. 

The Wind Hashira, Sanemi Shinazugawa, and his brother, Genya, have a strained relationship. This is because Genya once accused Sanemi of murdering their mother, though he was only protecting Genya after she had become a demon. Sanemi is very hostile toward Genya following this, and no longer considers him his brother and even threatens him when Genya tries to make amends. 

During a break in his training, Tanjiro witnesses first-hand the hatred Sanemi carries for Genya. In addition to brushing off his brother's apologies, he tries to gouge his eyes out when he learns Genya eats demons in order to become stronger. Despite Sanemi's position, Tanjiro cannot just stand aside; he pushes Genya out of the way. Though Sanemi confirms he isn't trying to kill his brother — that would be against the Corps' code — he admits he wants to injure him so badly that he would have to leave the organization. This results in a long-lasting brawl between Tanjiro and Sanemi, which has to be broken up. Tanjiro's part in the fight is not without consequence. He is banned from approaching Sanemi, and by extension, from the training course that the Hashira had set forth. 

It is disappointing he cannot take part in that trial, but Tanjiro has proven that he is plenty strong enough. It is even more heartbreaking that he is unable to reason with Sanemi and restore his relationship with Genya.