| SPOILER WARNING! This article contains spoilers from the manga |
|
|
|
|
|
|
- If I'm scum, then you're trash.
- —Zenitsu, to Kaigaku, in the Infinity Castle Arc
KaiZen is the slash ship between Kaigaku and Zenitsu Agatsuma from the Demon Slayer fandom.
Canon[]
Pre-Canon[]
Kaigaku and Zenitsu are both Thunder Breathing users who trained under Jigoro Kuwajima, the former Thunder Hashira, and were intended to be his joint successors. Both share similar origins as orphans who worked hard to meet their master's expectations. However, their relationship was strained due to their clashing personalities. Kaigaku resented Zenitsu, whom he saw as weak and overly emotional, while Zenitsu disliked Kaigaku for his harsh treatment and critical remarks. During Zenitsu's recollection in the Spider Mountain arc, Kaigaku is shown throwing peaches at Zenitsu and scolding him for his perceived incompetence.
Zenitsu had been training under Kuwajima for about a year, while Kaigaku had already passed the Final Selection before him. This timeline suggests they only spent a few months to half a year training together.
Infinity Castle Arc[]
In the Infinity Castle Arc, the two met once more. It was then revealed Kaigaku had become a demon and was now holding the position of Upper Rank Six. Kaigaku injured Zenitsu badly during their fight using a powerful move that combined Lightning Breath with a demon technique he gained after becoming a demon. This attack could destroy his opponent's body. However, Zenitsu defeated Kaigaku by using the Urushi-no-Kata, a technique he created specifically to fight alongside Kaigaku. This move cut off Kaigaku’s neck, ending their battle.
As Kaigaku’s severed head and Zenitsu’s unconscious body fall, Kaigaku is stunned by Zenitsu’s creation of a seventh form. He grumbles bitterly, unable to accept that someone he considered weaker had surpassed him in such a way. As his body begins to burn to ash, Kaigaku clings to his pride, refusing to admit defeat. He convinces himself that Zenitsu, now too weak to survive, will die alongside him.
In his final moments, a demon appears before Kaigaku. The demon tells him that someone who never gives cannot truly receive, and that wanting alone is meaningless without the effort to achieve. The demon goes on to say that dying alone is a pitiful fate. As Kaigaku disintegrates completely, the demon catches Zenitsu and leaps to safety.
Fanon[]
KaiZen enjoys a modest but dedicated following. Fans explore their dynamic through multiple lenses, portraying it as a romantic pairing, a familial bond, or a rivalry. Notably, the pairing is more commonly viewed as a romantic ship and holds greater recognition in the Eastern fandom, whereas in the Western fandom, it is more frequently depicted as a familial relationship.
In fanworks, there are numerous portrayals of Kaigaku and Zenitsu. Within the canon timeline, a popular trope involves the two fulfilling Jigoro’s vision by becoming the Thunder Pillars, or the Nari-Bashira together. Another common scenario depicts Zenitsu discovering Kaigaku after he has been turned into a demon and taking care of him, often with Kaigaku taking on a smaller, Nezuko-like form. Additionally, many fans enjoy dressing Kaigaku in a kimono matching Zenitsu’s, a gift from Jigoro that, according to canon, Kaigaku never wore.
Within reincarnation modern AU's and Kimetsu Academy AU's, many people enjoy portraying them as step siblings or training under Jigoro, with a more friendly relationship.
Fandom[]
- FAN FICTION
- Kaigaku/Zenitsu Agatsuma tag on AO3
- Kaigaku & Zenitsu Agatsuma tag on AO3
Trivia[]
- Zenitsu once hit a higher-ranking corpsman who spoke ill of Kaigaku.
