The full re-air of the Demon Slayer: Kimetsu no Yaiba anime series continued on June 21, 2026, with episode 12, “The Boar Bares Its Fangs, Zenitsu Sleeps.” Fans online were eagerly awaiting the moment when Zenitsu finally awakens, and the episode delivered.
The series, based on the manga by Koyoharu Gotouge, follows Tanjiro Kamado as he joins the Demon Slayer Corps to find a cure for his sister Nezuko, who was turned into a demon. The anime, produced by ufotable, began airing in April 2019 and has since expanded into multiple arcs, with the latest film trilogy Infinity Castle Chapter 1 releasing on July 18, 2025.
Note: The following contains spoilers for episode 12.
Inosuke Makes a Rough First Impression
In episode 12, Tanjiro finds himself in a strange mansion where the demon Kyogai can rotate rooms by beating his drums. He also encounters a mysterious boy wearing a boar’s head mask — Inosuke Hashibira. Inosuke immediately steps on a little girl named Teruko, prompting Tanjiro to throw him off. “It’s the first time I’ve been thrown by a human!” Inosuke exclaims.
Fans commented: “Early Inosuke is such a jerk lol,” “He’s so野蛮 at this point,” “Don’t step on Teruko-chan!!” and “It’s great to see Inosuke’s heart grow from here.”
Zenitsu’s Terrifying (and Hilarious) Struggle
Meanwhile, Zenitsu Agatsuma, separated from Tanjiro, is terrified while dragging along Teruko’s brother Shoichi. He trembles at every word and when a demon appears, he screams and runs away. “It’s Zenitsu’s turn www,” “Shoichi is so fed up with him,” “Normal Zenitsu is hopelessly unreliable,” viewers laughed.
Despite his cowardice, Zenitsu tells Shoichi to run and leave him behind, but when Shoichi refuses, Zenitsu tearfully says he has to do something — then promptly falls asleep as the demon approaches.
Fans noted: “Even though he’s scared, he still protects the kid,” and “From the start, he never abandons people.” Anticipation built: “Here it comes!” “What comes next is amazing, Zenitsu!” “He’s asleep — here we go!”
“Here It Is!! Zenitsu Awakens!!”
When the demon attacks with its long tongue, Shoichi screams for Zenitsu to wake up. With eyes still closed, Zenitsu rises and mutters, “Thunder Breathing, First Form: Thunderclap and Flash,” and in an instant beheads the demon.
Reactions exploded: “Here it is!! Zenitsu awakens!!” “The gap is insane…” “This is why I love Zenitsu!” “But then he’s noisy again,” “Zenitsu is definitely the cutest in Demon Slayer,” “He’s the ideal man who only comes through when it really counts.”
When Zenitsu comes to, he has no memory of the feat and panics: “He suddenly died! What’s going on? I hate this!” — back to his usual self.
@anime_kimetsu_official Thunder Breathing, First Form: Thunderclap and Flash | Kimetsu no Yaiba: Tanjiro Kamado, Risshi-hen Episode 12 “The Boar Bares Its Fangs, Zenitsu Sleeps” Infinity Castle Chapter 1 now in theaters nationwide from July 18 (Fri)! #鬼滅の刃#DemonSlayer#無限城編#InfinityCastle#アニメ#映画#anime Original Music – Anime “Demon Slayer” Official
“Tanjiro’s Big Brother Energy Is Amazing”
Elsewhere, Tanjiro senses an unusual blood scent and finds Teruko’s other brother, Kiyoshi. Kiyoshi explains that he was captured by demons because of his rare blood (marechi). The demons fought over who would eat him, and Kyogai dropped a drum that Kiyoshi picked up. By beating the drum, he could rotate rooms and escape.
Fans praised Tanjiro as he applied medicine to Kiyoshi’s wounds and spoke gently: “Tanjiro’s big brother energy is amazing,” “He’s like Doraemon pulling out medicine,” “I love how he speaks kindly so as not to scare him,” “Tanjiro’s injuries are worse but he still cares for the kids.”
Tanjiro tells Kiyoshi and Teruko to use the drum to move rooms as soon as he leaves, promising to come back for them. He encourages them: “You can do it, right?” “Good. You’re strong.”
“Tanjiro’s Famous Line Is Here!!”
Finally facing Kyogai, Tanjiro’s body is battered. He thinks: (Lady Tamayo treated me, but my injuries aren’t healed. Can I win? The pain is unbearable!) He recalls: “I’ve been enduring this whole time! When I pulled Zenitsu off that girl, when I raised my voice — it hurt so much! I endured because I’m the eldest son. If I were the second son, I couldn’t have endured.”
Fans erupted: “Tanjiro’s famous line is here!!!” “Tanjiro’s weird logic — he endured because he’s the eldest son,” “This self-encouragement is my favorite line,” “Natsuki Hanae’s passionate performance makes it a legendary scene,” “‘I endured because I’m the eldest son’ is too amazing lol.” Some added: “Tanjiro’s eldest-son/second-son theory… normally even an eldest son couldn’t endure that.”
Despite his injuries and dark thoughts, Tanjiro recalls Sakonji Urokodaki’s words, steels himself, and grips his Nichirin blade: “I will never give up!”
Cast Comment: Kiyoshi’s Voice Actor Junichi Toki
For the re-air, the official Demon Slayer account is posting weekly cast comments. For episode 12, Junichi Toki, who voices Kiyoshi, shared his thoughts: “Honestly, I never thought I’d get to comment. When I visited the recording studio, I felt the main cast giving their all, and I remember playing Kiyoshi with everything I had at the time, determined not to break that world.”
Additionally, ufotable shared the cover of the script from that recording session, highlighting the contrast between Tanjiro and Zenitsu.
Next Broadcast and Staff/Cast
The next episode, “Something More Important Than Life,” will air on July 5 at 9:30 AM (JST) on Fuji TV and other stations. There will be no broadcast on June 28.
Cast:
- Tanjiro Kamado: Natsuki Hanae
- Nezuko Kamado: Akari Kito
- Zenitsu Agatsuma: Hiro Shimono
- Inosuke Hashibira: Yoshitsugu Matsuoka
Staff (Risshi-hen / Tanjiro Kamado, Risshi-hen):
| Role | Name |
|---|---|
| Original Creator | Koyoharu Gotouge |
| Director | Haruo Sotozaki |
| Character Design / Chief Animation Director | Akira Matsushima |
| Sub Character Design | Miyuki Sato, Yoko Kajiyama, Mika Kikuchi |
| Script Production | ufotable |
| Concept Art | Koji Eto, Masaru Yachu, Kasumi Takeuchi, Yuri Kabasawa |
| Director of Photography | Yuichi Terao |
| 3D Director | Kazuki Nishiwaki |
| Color Design | Yuko Ohmae |
| Editor | Manabu Kamino |
| Music | Yuki Kajiura, Go Shiina |
| Production Producer | Hikaru Kondo |
| Animation Production | ufotable |
| Opening Theme | LiSA “Gurenge” (SACRA MUSIC) |
| Ending Theme | LiSA “from the edge” (SACRA MUSIC) |
Staff for subsequent arcs (Mugen Train, Entertainment District, Swordsmith Village, Hashira Training) follow similar credits with different theme songs and minor changes. Full details are available on the official website.
(C) Koyoharu Gotouge / Shueisha, Aniplex, ufotable
