Demon Slayer: Infinity Castle finally unveiled the promo visual that Zenitsu fans have been waiting for. After the exciting promotions highlighting Tanjiro Kamado and Giyu Tomioka’s fight against Akaza, as well as Shinobu Kocho facing off against Doma. Now that the U.S. release date is closer than ever, the anime finally drops the visual of Zenitsu fighting Kaigaku, a new Upper Moon Six. Zenitsu has been making headlines since the Hashira Training Arc, after his demeanor completely changed when he read a strange letter. The person who used to freak out at every minor inconvenience is uncharacteristically calm, so it’s clear something unbelievable must have happened.
Videos by ComicBook.com
He didn’t even flinch while falling into the Infinity Castle when everyone else was surprised. Manga fans already know about everything that will take place in the castle, and there’s no doubt that Ufotable has elevated the fight even more with stellar animation. Kaigaku’s face and rank weren’t revealed in the original trailer, and we only saw Zenitsu looking menacingly at his opponent. There’s a grudge to settle between the two, and the once goofy Demon Slayer has every reason to put the demon down with his own hands. As far as the villains in Demon Slayer go, a lot of them are somehow pitiful because of their tragic pasts. However, Kaigaku is definitely the most disliked demon in the series, and rightfully so.
Warning: Spoilers Ahead From the Demon Slayer Manga!
Zenitsu and Kaigaku Were Fellow Disciples Under the Same Master

Kaigaku was briefly introduced in Zenitsu’s backstory during the first season. He looked down on his fellow disciple for not being able to use the other Thunder Breathing forms except for the first one. Being taught by the former Rumble Hashira (a title given to a Hashira who uses Thunder Breathing), Kaigaku and Zenitsu eventually became Demon Slayers but went down two different paths. While Zenitsu continued to fight for the good of the people, Kaigaku gave up on his humanity and chose to become a demon.

He couldn’t care less about the fact that his master, Jigoro Kuwajima, committed seppuku as an act of atonement for training Kaigaku. Demon Slayers are capable of using Breathing Techniques that grant them enough power to defeat other demons. If people like them were to transform into demons, one can imagine the devastating powers they will be able to possess. Not to mention the very act of abandoning one’s humanity in itself is considered unforgivable. Of course, Kaigaku became a demon to save his life, but he never considered the consequences of his own actions.
Even when he was living with Gyomei, and caused the deaths of all the children the Stone Hashira was taking care of, Kaigaku never felt an ounce of guilt. The letter that completely changed Zenitsu carried news of his master’s death and the tragic reason behind it. Zenitsu swore to set things right and put an end to Kaigaku with his own hands.
Are you excited for Zenitsu’s biggest fight in Demon Slayer: Infinity Castle? Let us know in the comments below!








