Demon Slayer is getting more and more popular and could become one of the most popular animes ever. Since it came out, its sad story of humans vs demons has captured the minds and hearts of fans all over the world. It has a lot of intense sword fighting, fabulous special skills, and appealing animations. In this post, we will see who kills Kaigaku, the Upper Moon Rank Six?

Kaigaku is the Upper Moon Rank Six in Demon Slayer: Kimetsu no Yaiba. He takes the position of Upper Moon Rank Six after the death of Daki and Gyotaro.

Who Killed Kaigaku?

Zenitsu Agatsuma, one of the thunder-breathing users, kills Kaigaku in an intense fight. He used Thunder Breathing Seventh Form: Honoikazuchi no Kami to kill Kaigaku. Kaigaku was the former senior of Zenitsu, and they both learned sword fighting under the same senpai.

The battle between the two sword fighters takes place in the Infinity Castle in Demon Slayer.

Zenitsu runs into Kaigaku as he walks through the castle. He hears Kaigaku talking from behind a door. He tells him to come out because he knows it’s him. Kaigaku doesn’t like how Zenitsu talks to him like he’s not his senior, so he tells him to stop spewing nonsense words.

Zenitsu says that, now that he is a Demon, Kaigaku is no longer his senior. Kaigaku makes fun of Zenitsu, saying that he looks bad and is still just a weakling. He then tries to anger Zenitsu by asking if he has become a Hashira or if he can use Thunder Breathing in a form other than the First Form. Zenitsu responds calmly that Kaigaku seems happy to be the lowest-ranked Upper Rank, even though he’s just filling an empty spot.

The Underlying Anger

Zenitsu shamed Kaigaku for his actions by Wiki

Kaigaku laughs and says that he now knows how to talk back after Zenitsu insults him. Zenitsu wants to know why Kaigaku turned into a Demon since he used to be very interested in learning Thunder Breathing and becoming the successor to the previous Thunder Hashira.

He then tells Kaigaku that he was the reason their master, Jigoro, died because Kaigaku turning into a Demon was the reason he killed himself and died a slow, painful death on his own. Kaigaku says that he thinks only people who know his worth should care about him. He then makes fun of Jigoro by calling him a “senile old man.” Zenitsu gets furious after hearing these words about his master.

Kaigaku gets even angier at Zenitsu’s words. He unsheathed his sword and went straight away to kill Zenitsu. He tries to kill Zenitsu with his improved Thunder Breathing, Fourth Form: Distant Thunder, which he got from the Blood Demon Art.

Kaigaku vs Zenitsu
Kaigaku vs Zenitsu

Zenitsu, quick as he is, pulls out his sword and cuts past Kaigaku’s neck, calling him trash and saying he was too slow. Kaigaku sees that Zenitsu is a much better swordsman and has a lot more skills than he did before. But he still thinks that Zenitsu, no matter how hard he trains, will never be able to beat an Upper Rank like him.

Who is Better? Kaigaku or Zenitsu?

Kaigaku then uses Thunder Breathing, Second Form: Rice Spirit, to cut Zenitsu. Zenitsu says that Kaigaku has eaten too many people and asks him if he doesn’t know what is right and wrong. Kaigaku proudly says that he does know what is right and wrong.

As Kaigaku uses Thunder Breathing, Third Form: Thunder Swarm, he says that those who judge him correctly and accept him for who he is are right, and those who don’t accept him are wrong. Kaigaku then uses Thunder Breathing, Fifth Form: Heat Lightning, and teases Zenitsu while praising his own Blood Demon-enhanced Forms. He says that when his Thunder Breathing forms cut Zenitsu’s body, his skin and flesh burn and break apart as he uses the Thunder Breathing, Sixth Form: Rumble and Flash.

Zenitsu killing Kaigaku by using Thunder Breathing, Seventh Form: Honoikazuchi no Kami
Zenitsu killing Kaigaku by using Thunder Breathing, Seventh Form: Honoikazuchi no Kami

Zenitsu, hurt by the constant attacks, thinks about his past relationship with Kaigaku as he falls. He thinks about how he and Kaigaku did not get along. He realizes that Kaigaku is not someone he knows. After that, Zenitsu jumps up on a wall and uses his own developed Thunder Breathing Form: Thunder Breathing, Seventh Form: Honoikazuchi no Kami. Kaigaku’s head is cut off as he falls, and Zenitsu curses him as they both fall.

Zenitsu proves that he is the better Thunder Breathing User and worthy of carrying the name of Thunder Hashira, Jigoro.

Zenitsu Die After Fighting Kaigaku?

No, Yushiro comes into the castle at the most crucial time. He saves Zenitsu when he falls. Yushiro makes fun of Kaigaku by telling him that it is sad to die alone.

Kaigaku has a horrible death, and Zenitsu is saved. While Yushiro is treating Zenitsu, he falls asleep and wakes up in a dream world where he sees Jigoro. As he tells Jigoro he’s sorry he couldn’t get along with Kaigaku, Jigoro looks up at him and says, “Zenitsu, you are my pride and joy.”

Final Thoughts – Who Killed Kaigaku?

The battle between the two students of former Thunder Hashira, Jigoro, is one of the most intense and thrilling so far. The anger towards each other, the history and the matching skills make it even more enjoyable.

In the end, to answer the question, who killed Kaigaku? It’s Zenitsu, the Thunder Breathing Demon Slayer.

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About the Author

Logan Rane

Hey, I'm Logan, and I love anime and manga. I could talk about them all day, write about them non-stop, and watch them around the clock. I've watched hundreds of animes and read thousands of mangas at this point in my life - so you could say I'm pretty deep into it all.

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