Demon Slayer Unveils Zenitsu’s Opponent & He’s the Worst Demon in the Series

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As an observer, I’m thrilled to share that the long-awaited promotional visual for Demon Slayer: Infinity Castle has finally been revealed, particularly focusing on Zenitsu’s battle against a new Upper Moon Six – Kaigaku. Following the electrifying previews featuring Tanjiro Kamado and Giyu Tomioka’s encounter with Akaza, as well as Shinobu Kocho battling Doma, this latest visual drop heightens the anticipation as the U.S. release date draws nearer.

Since the Hashira Training Arc, Zenitsu has garnered significant attention due to his remarkable transformation after reading a peculiar letter. The individual who once panicked over the slightest hiccups now exhibits an unusual calmness, hinting at some extraordinary event that must have taken place.

He remained unmoved as he plunged into the Infinity Castle, despite everyone else being taken aback. Manga enthusiasts are well-aware of the events unfolding within the castle, and it’s clear that Ufotable has made the fight even more thrilling with exceptional animation. The identities of Kaigaku and his rank weren’t disclosed in the initial trailer, and all we got was Zenitsu glaring at his adversary. There seems to be a score to settle between them, and given his motivations, it makes perfect sense for Zenitsu to defeat the demon personally.

In the Demon Slayer series, many villains elicit sympathy due to their tragic backgrounds. However, Kaigaku is arguably the most despised demon, and for good reason.

Warning: Spoilers Ahead From the Demon Slayer Manga!

Zenitsu and Kaigaku Were Fellow Disciples Under the Same Master

During Zenitsu’s initial storyline in the first season, a character named Kaigaku was briefly introduced. Initially, Kaigaku held his fellow disciple in contempt because he could only master the first Thunder Breathing form. As students of the former Rumble Hashira, they both eventually became Demon Slayers, but their paths diverged significantly. While Zenitsu remained dedicated to protecting humanity, Kaigaku renounced his humanity and opted to transform into a demon instead.

He showed no concern whatsoever that his master, Jigoro Kuwajima, performed seppuku as a penance for teaching Kaigaku. Demon Slayers can utilize Breathing Techniques, which grant them sufficient power to vanquish other demons. If individuals like them were to metamorphose into demons, it’s easy to envision the destructive powers they would acquire. Additionally, giving up one’s humanity is viewed as unforgivable, so it’s understandable that Kaigaku didn’t ponder the repercussions of his actions after turning into a demon, even though he did so to save himself.

In simpler terms, while living alongside Gyomei, Kaigaku was responsible for the loss of all the children he was guarding, yet he never felt remorseful about it. A letter that reached Zenitsu announced his master’s passing, along with a heart-wrenching explanation. Moved by this, Zenitsu vowed to take matters into his own hands and bring justice upon Kaigaku.

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2025-09-05 17:42