Nightmare Fuel / Demon Slayer: Kimetsu no Yaiba

Beware Of Spoilers. All spoilers on this page are left unmarked. You Have Been Warned!

She really shouldn't have blurted out Muzan's name.

It's called Demon Slayer for a very good reason.

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In General

• The entire premise of the manga is that evil demons are inhabiting and invading Japan. Terrifying, monstrous, bloodthirsty creatures that come out during the night in search of human prey. The saddest (and scariest part) about it? Demons that were once human beings. As soon as they become demons, they can either devour you alive or turn you into a demon yourself. If you're not a Demon Slayer, you have no way to defend yourself or your family from a demon, and if you're attacked, you better pray for a quick death. If you become a demon, you are instantly filled with a primal instinct to kill and devour that will cause you to see anyone as food, including innocent bystanders and your own family members. You will also gradually lose your original personality and memories. Even the Demon Slayer Corps regularly lose many of their swordsmen to demon attacks, because they are just that powerful.
• And who's the one responsible for all the demons that terrorize Japan? The Demon King, Muzan Kibutsuji. Everything about that monster is pure nightmare fuel at its finest. The guy is a living sociopathic monster with a lot of mental issues. And we mean, a lot of issues. From his nasty temper, his narcissistic personality, and his strong lack of empathy and kindness towards others, Muzan is one demon you would NEVER want to come across. Because the guy is so deranged in his mind and is just so incredibly petty in general, he would do things you would likely or not likely expect him to do. On one hand, he might turn you into a demon. On the other hand, he would just kill you brutally. Either way, it would not be a merciful sight to witness. If you want a prime example of nightmare fuel in this series, then Kibutsuji is your lucky guy. Each folder regarding him can be found and they will not be pleasant to read about.

Final Selection Arc

• Tanjiro coming home to find that his entire family - mother and siblings, the youngest of whom can't have been much older than six or seven - were bloodily slaughtered by a demon. Only Nezuko is alive, but as he tries to carry her to help, she transforms into a demon herself and attacks him; if his pleading hadn't gotten through, she easily could've killed him.
• The ways Sabito and Makomo were killed by the Hand Demon during the Final Selection: Makomo has her limbs ripped off while Sabito's head is crushed.
  • The Hand Demon, upon finding out just how much time has passed since it was trapped in the Final Selection area, is genuinely angry, raging about how it had been tricked into this place and could never escape and swearing vengeance. However, it gives the reader a healthy dose of Fridge Horror when you realize that this demon has been locked in that area for decades and has been killing potential Demon Slayers all of that time. An enemy that would give even a veteran Demon Slayers problems due to its size, the thickness of its neck, and how much protection it has around said neck, had just been sitting around in a region where inexperienced children were thrown at it on a regular basis, with no one bothering to do anything about it. How many dozens of children had this demon slain up until it was finally stopped?

First Mission Arc

• We get a glimpse of how dangerous Muzan Kibutsuji is when the Swamp Demon becomes incredibly fearful when Tanjiro asks him for information about Muzan as otherwise the demon was quite confident.
  • The way the demon panics and breaks, repeatedly shouting "I can't!", as soon as Tanjiro asks him information about Muzan. It shows that the majority of the demon race greatly fears the man very much, and those who know of him and see his face? They have to keep quiet or something terrible happens to them.

Asakusa Arc

• Tanjiro runs after Muzan and finds him, with the latter impersonating a human man who has a wife and a child. Tanjiro is sickened by the fact that the wife and child cannot tell that Muzan is a demon. Muzan uses his demon claws to turn a man who was passing by into a demon, who starts biting his wife much to Tanjiro's horror.
• After his encounter with Tanjiro, Muzan finds a group of people in an alleyway that mock him for his pale skin. While he kills the two men quite fast, he injects the girl that was with them with his blood. The results aren't pretty at all. Her body contorts with horrible fleshy sounds before boiling from the inside out, graphically reducing her to red soup. This also counts as Nausea Fuel.
• The Temari Demon Susamaru throws her temari balls, one of which completely shreds Yushiro's head. Luckily, he is a demon so he heals but it's initially only the lower part of his head.
• The reason why the first few demons Tanjiro encounters are so hesitant to name their master? After Susamaru reveals Muzan's name to Tamayo and Yushiro, Muzan's cells take hold of her and three large arms came out from her mouth, chest, and stomach, which then rip her to shreds until there's nothing left of her.
  • The worst part? Doing this is completely pointless. His greatest threat, The Demon Slayer Corps, already knows his name, and there's no indication the majority of demons even know anything about Muzan's abilities and weaknesses that would be worth divulging. Muzan is just so impossibly paranoid and so completely uncaring about the lives of his servants that he'd rather they all die in horrible agony than risk giving his enemies the slightest possible hint of how to stop him. Now one could fully understand why the swamp demon was scared shitless of Muzan.

Natagumo Mountain Arc

• A demon slayer manages to get out of the forest of the mountain but is pulled back by the Mother Spider Demon and gruesomely killed.
• The techniques of the Spider Demons:
  • The Mother Spider Demon manipulates the other slayers with her threads to kill each other, with Murata being the only survivor, then she manipulates the half-dead corpses of other Demon Slayers to attack Tanjiro and Inosuke; they beg for death the entire time, one with his arms broken in several places yet still holding his sword, and just when it looks like they've found a way to fight back without killing them by hanging them off trees, she snaps their necks. Tanjiro is so angry about this that Inosuke can feel it despite not looking at him.
  • The Elder Brother, a giant spider with a human head, uses poison to painfully transform people into spiders themselves. The victims lose their hair, become unable to move, lose consciousness, then when they wake up they become spiders.
  • The Father is a rampaging berserker with a spider's head who, after shedding his skin and taking on an even more monstrous form, nearly crushes Inosuke's skull.
  • The Older Sister's Ball of Yarn traps people in it and secretes a solvent which first melts the clothes of those trapped, then the people themselves. Shinobu points out she saw dozens of them on the way up the mountain.
  • The main source of it is Rui, Lower Rank 5. He can manipulate threads to severely injure other people.
    • Rui is disguised as the family's youngest son, but it turns out they aren't really his family, just an assortment of other demons he's manipulated into playing the roles.
    • The anime adds a scene that shows the Sister's transformation, and while it thankfully cuts away at the last second, it's clear that he was digging his fingers in to rip her face off.
    • If any of them fail to play their roles, he either tortures them himself or has the others do it; the Mother already lives in paralyzing fear of the Father because of this (and her original form is later revealed to be that of a small girl who was clearly younger than even Nezuko when she became a demon).
    • Really, Rui is terrifying all by himself, despite his young age. He is a Control Freak who believes that family members should play the roles they are meant for, including being willing to die for each other without hesitation, and that if they cannot fulfill those roles, they should just die as they are not worth anything. To that end, he transforms other demons to look like him and forces them to play the roles of his family, punishing (and in some cases, even killing) them when they do not comply. His behavior is like a child who gets upset and throws a tantrum when their playmates don't follow the rules of their game, only he is a demon child with the power of a Blood Moon. Even more unnerving is the fact that his voice never raises even when he gets visibly angry or agitated.
• The Father Spider Demon slowly crushing Inosuke's skull during their battle.
• After seeing Nezuko protect Tanjiro from his threads, Rui decides to take Nezuko for himself and form a bond of terror with her and make her regret if he does not do what he asks. Tanjiro is understandably angered.
• Rui gets hold of Nezuko and traps her in his threads, and she is bleeding all over. Then Rui tells Tanjiro that he will let her bleed for a while and that if she does not become more docile, he will let her there until daybreak to burn in the sun.
• Rui's curbstomping of Tanjiro with the latter unable to land a single hit.
• When Nezuko struggles against Rui's threads, he attacks her without any hesitation, and she bleeds heavily from her right leg.
• When it looks like Tanjiro beheaded Rui, it turns out that Rui cut off his own neck with his threads and is really pissed off, vowing to kill Tanjiro and Nezuko.
• In the flashback to Rui's past, after the Older Sister is turned into a demon, another sister spider tells her that both of them can run away when Rui is summoned by Muzan since she was fed up with Rui's treatment. However, the Older Sister told Rui about it, and Rui traps the other sister in his threads until sunrise heavily bloodied and burns away.

Rehabilitation Training Arc

• The Hashira putting the Kamado siblings on trial and deciding whether or not Nezuko should be allowed to live because she is a demon, while Tanjiro is so badly wounded from his fight with Rui that he can't physically do anything to protect her and can only plead with them to spare his sister's life. (And even if he was in fighting shape, there would be no way for him to protect her from all nine Hashira if they decided to kill her.) Even though they have reason to worry about the possibility of her becoming bloodthirsty and devouring humans, this is still a group of people deciding whether or not to kill a little girl in front of her older brother. Uzui expresses a willingness to do the honors of decapitating Tanjiro if he's found guilty, and Sanemi is especially eager for an excuse to kill Nezuko, breaking open her box, cutting open his own arm, and trying to tempt her into tasting his blood.
  • Urokodaki's letter vouches for Nezuko's good behavior. However, it also says that if she eats human blood, then he, Tanjiro, and Tomioka will atone through commiting ritual suicide by disemboweling.
• Muzan deciding to kill the remaining Lower Ranks Demons in gruesome fashions after Rui's death: Kamanue and Mukago are eaten alive, Wakuraba is decapitated when he tries to escape, and we aren't even shown what happens to Rokuro. However, the true terror is the intimidation factor. Muzan is revealed to have the power to read his servants' minds, allowing him to find a way to turn their thoughts into an excuse to execute them no matter how much they beg, cry or try to flee.
  • Only Enmu is spared after declaring his loyalty to Muzan and that he is grateful to die at his hands. Muzan's response is to inject him with his blood to give him more power, pleased to hear this.

Mugen Train Arc

• Enmu, Lower Rank One, attacks the party in their dreams with the goal of destroying their 'spiritual cores' and rendering them living corpses; while he shows them pleasant images, his dialog with Tanjiro makes it clear that he could have plunged them into horrific nightmares instead. And then he manages to fuse with the train they're riding on, so that his insides begin absorbing hundreds of other sleeping passengers. It takes a lot of effort from the main cast to save everyone on the train.
• At one point in their fight Enmu after trying and failing several times to put Tanjiro back inside the dream world, he forces Tanjiro into a nightmare with his entire family (including his father, even though he died long before they did) returned as bloodied corpses blaming him for their deaths, complete with a hellish atmosphere. No doubt an attempt to trigger Tanjiro's guilt and trauma. But this backfires horribly as Tanjiro easily breaks out of the nightmare with pure rage and lashes at Enmu for having the audacity to do such a thing and goes for the kill.
  Tanjiro: THERE'S NO WAY THEY WOULD EVER SAY THAT!!! NOT EVER!! NOT MY FAMILY!! DON'T YOU DARE! INSULT! MY FAMILY!!!
• The fact that an even stronger demon showing up in the form of Akaza is haunting enough. If not for Kyojuro being Defiant to the End, stalling for the sun to come up if killing him was an option, the demon would have killed everyone else in the vicinity.
• Akaza punches Kyojuro's left eye, making him unable to use it.
• The way Akaza kills Kyojuro at the end of arc: impaling him through the chest with his hand.

Red Light District Arc

• The Arc Villain of this part is the Upper Moon 6, Daki. A beautiful but utterly vicious oiran who worked her way to the top of the Entertainment District, harassing and bullying many of her fellow workers to the point of suicide just because they annoyed her, and abusing a very young girl working in the Kyogoku House for the simple offense of her room not being clean. In the past, she has killed and devoured no less than seven Hashira, and by the end of her fight with the Demon Slayers, the entire Entertainment District has been reduced to smoldering piles of wood and rubble.
• Daki remorselessly pushes the Oiran, Omitsu, through an open window to fall to her death simply because she was pissed off.
  • Then we see her bloody corpse found by the others...
• A civilian interferes during Tanjiro's fight against Daki, annoyed by the noise outside. Daki attacks him as well as the surrounding buildings with people inside with her obi and Tanjiro tries to protect him, but the sashes end up injuring Tanjiro while cutting off the man's hand. Tanjiro is so enraged by this that Tears of Blood fall from his eyes.
  • The anime adaptation ramps up this particular moment through Daki demolishing the entire corner of the street they were fighting on—with no small amount of casualties.
  • Tanjiro's Unstoppable Rage (triggered by Daki's sheer callousness), in turn, does not only involve his bloody tears, but also full-on Wide Eyes and Shrunken Irises. He then methodically and swiftly parries and slashes through Daki's sash tentacles and limbs with nary a word utterred. Watching usually kind-hearted and compassionate Tanjiro in combat with a permanent Death Glare, with the movement efficiency of a Terminator is very unsettling to watch. This is later explained to be him essentially autopiloting Sun Breathing, in the high of combat, which the memory of his dead siblings had to break him out of because he's forgotten to breath.
  • There's also a minor but important note from the demon's perspective: with Daki realizing Tanjiro's shift in attitude and sheer rage, she realizes Muzan's blood cells is triggering in her a Genetic Memory of another swordsman, with a similar forehead scar and earrings as Tanjiro, delivering a "The Reason You Suck" Speech (in Kazuhiko Inoue's baritone) not unlike Tanjiro's angry rant, about to come for their head. Viewers in the know would recognize this man as Yoriichi Tsugikuni, the founder of the Demon Slayers who haunted Muzan since the beginning.
• Chapter 83: Nezuko's new demon form starts to take her over as she proceeds to utterly brutalise Daki with uncharacteristically sadistic glee, stomping her into the ground while maniacally laughing.
• Chapter 84: Daki cuts off Nezuko's arms, legs, and also her head. Nezuko's spilled blood then forms into a free-floating non-Newtonian fluid that keeps the appendages technically attached and summons them back into place.
  • After kicking Daki through a wall, Nezuko notices a wounded courtesan near her, sees blood dripping from her wrist and lunges at her. Tanjiro has to hold her back by the teeth with his blade while she frantically tries to break free.
  • To make matters worse, Daki's gotten back up; much of her skin (including half her face) is still regenerating from the beating Nezuko gave her. Her face is so screwed up that her teeth are completely bared and her facial muscles only twitch in the attempt of her making an angry expression. This makes it even worse as she slowly walks toward the Kamado siblings to rip them apart.
• Chapter 85: Daki's brother Gyutaro emerging, nay, growing out of his sister's back like a tumor.
  • It doesn't really help how at first it was funny after Daki got decapitated and started crying. But when she yells for her brother, then it is no longer funny when Gyutaro emerges.
• Chapter 86: Gyutaro is so envious of Uzui that he threatens to skin him alive and spill his innards.
• Chapter 92: Inosuke's Sixth Fang: Palisade Bite involves him sandwiching a target's neck between his blades and then grinding his swords through like saws to decapitate them. Admittedly, the target is still Daki, but the brutality and psychological terror it causes is very effective in their simplicity. It's also appropriate to note that "death by sawing" was actually an option in historical real-life executions, if not necessarily in Japan.
  • After Inosuke cuts off Daki's head and runs away with it, Gyutaro suddenly stabs him through the chest with one of his sickles.
  • Uzui is seemingly dead due to the poison from Gyutaro's earlier attack, and he lost his left hand courtesy of an earlier clash with the Waxing Six.
• Chapter 92-94/S2E10: The episode, being the climactic moment of the fight against Daki and Gyutaro, involves a significant amount of stylistic Gorn.
  • The episode starts out with Tanjiro and a still-sleeping Nezuko left behind in the wreckage of a now-burning Yoshiwara. The fiery abandoned scenery (not to mention the realistic tone of the flames is near-evocative of the climactic carnage of another ufotable production, the Great Fuyuki Fire of Fate/Zero).
  • Gyutaro petting Tanjiro and seemingly commiserating about his inability to defend his last living family member while cradling the youth's right hand. Then he crushes every bone of Tanjiro's first two fingers with ridiculous ease.
  • The Waxing Six then threatens Tanjiro with an ultimatum, become a demon or he will beat Nezuko to death.
  • During their attempt at finally subduing him, Gyutaro punctures Uzui's side and slashes out his left eye. Then as Uzui spear charge pins him, Tanjiro tries to get the fatal swing in, but Gyutaro stabs up under Tanjiro's chin with his remaining sickle, the blade hooks between his jaw and protrudes from his tongue and mouth.
  • When Tanjiro pushes through in beheading Gyutaro, his Demon Slayer mark awakens on his forehead—coupling with him pulling a rage-filled face that can only be described as awe-inspiring and simultaneously terrifying◊.
  • Despite them finally succeeding in beheading both Daki and Gyutaro simultaneously, the latter's now-headless body manages to release a massive swarm of his Rotating Blood Slashes. The resulting explosions ends with the entire block blowing up—while Tanjiro is dying of poison and his injuries. The air is sombre enough that the closing credits just run, with just the orchestra, as the burning carnage goes on.
• Chapter 96: Ume/Daki and Gyutaro's past turns out to be even worse than Rui's, with Nightmare Fuel and Tear Jerker in equal parts. Their mother was a prostitute in the poorest area of the Entertainment District (by the way, such environment is Harmful to Minors for Gyutaro and later Ume), who hated her son for being born a boy because it was bad for her line of work, and abused him to make herself feel better. She fed him so little that he had to eat mice and insects to survive, and other children would bully him and throw rocks at him because he was so ugly. When Ume was born, their mother was jealous of her beauty even when she was just a baby, and once tried to cut her hair off, only being stopped by Gyutaro. Their shit of a mother died via syphilis and knowing this illness, it is pretty much bad way to go. When Ume turned thirteen and was training to become a courtesan, she stabbed out the eye of a samurai who tried to assault her and insulted her brother, and in retaliation, she was bound hand and foot, burned alive, and thrown into a shallow grave. She was burnt to a crisp but still alive when her brother returned home.
  • As Gyutaro cradles her dying body, shrieking how he'll kill the gods for this last in his life's long list of injustices, the one-eyed samurai slashes him down the back, egged on by the madam. Gyutaro snaps fully and ice-pick hammers her face in before splitting the samurai from chin to forehead, killing him.
  • Gyutaro flees away with Ume's charred figure in his arms, and as they are about to die out in the elements, they have to meet the worst person possible to save them: a gleeful Doma comes across them, while he snacks on a courtesan's body-parts, and offers to turn them into demons.

Swordsmith Village Arc

• Chapter 106: While not as scary as Gyokko, Hantengu (Upper Moon 4) is nevertheless a very creepy and admittedly odd demon. For starters, he takes the form of a elderly man, who's always crying and shivering in fear, even to the smallest of things, and he also has a big bulge on his forehead, further adding the creepiness of his appearance. This would rather confuse the audience on why he's even the fourth-ranked upper demon in the first place, considering that his appearance and cowardly personality in general makes him look like a weak demon. That is until until he and Gyokko attacks the swordsmith village that he shows the audience why he's Upper Moon 4 in the first place.
  • The way Hantengu enters the room where Tanjiro, Nezuko, and the Mist Hashira, Muichiro Tokito are in. He simply just slides the door open and creepily crawls in, all while shivering and whimpering in fear, with tears in his eyes. The creepy part about this is that Tanjiro and Muichiro didn't even seem to notice him until he entered the room. Tanjiro, who's noted to have an incredible sense of smell, couldn't smell the scent of Hantengu until he entered inside the room. This further enhances the danger Hantengu actually represents despite his appearance and cowardly persona.
  • Muichiro manages to slice off the demon's head, so victory, right? Well, it was greatly doubtful, since A. Hantengu was rather defeated too quickly, which quickly rose suspicion. B. Tanjiro notes that despite slicing off an Upper Rank demon's head off, they don't usually die that easily, as best seen with Daki, which quickly cause Tanjiro to warn Muichiro that something was up. His (As well as the audience's) deduction were proven correct, as Hantengu suddenly split into two, with one regenerating his head back, while the other gain a body. Muichiro goes to attack one, but he suddenly lifts a leaf-fan and lifts it down at Muichiro. It stops for a quick second, before Muichiro is suddenly blown away from a strong gust of wind projected by the leaf-fan. After the wind, Tanjiro and Nezuko comes to face-to-face with Hantengu's clones: Sekido, the personification of Hantengu's anger and Karaku, the personification of Hantengu's pleasure.
    • Sekido's Blood Demon Art allows him to generate electricity that comes from his Khakkhara, simply by stabbing it into the ground surface. This attack greatly damages his enemies and even paralyzes them, even when they are in mid-air, and they can quickly lose consciousness. This is best demonstrated when he first uses his attack on Tanjiro and Nezuko, where they get paralyzed by his attack and nearly lose consciousness. If not for Genya's rescue, they would've been easily killed by Hantengu's clones.
    • Karaku's Blood Demon Art allows him to generate wind from his Uchiwa fan. His wind attack are dangerously powerful, as they can leave gigantic craters, level down entire buildings, and leave demon slayers and demon alike under its immense and powerful pressure, even knocking them unconscious. Combine that with Karaku's thrill of battle, you pretty much got a very dangerous demon whose power is just as strong as Sekido's.
  • Despite Genya's rescue, he unknowingly made the mistake of decapitating Sekido and Karaku, since they again split into two more demon clones: Aizetsu, the personification of Hantengu's sorrow and Urogi, the personification of Hantengu's joy, who also has wings on his back, allowing him to fly. This pretty much made the fight against Hantengu far more harder, as they are growing increasingly stronger than ever, with Tanjiro, Nezuko, and Genya getting ton of damages from the clones.
    • Aizetsu's Blood Demon Art allows him to project the thrusting attack of Yari over great distances, allowing the demon to attack from afar. Besides that, its potency is shown to be enhanced, as best seen when Genya, protecting Tanjiro from Aizetsu's Weeping Spears, which projects multiple long-ranged attacks, has majority of his body badly damaged from the technique. Aizetsu may not be as strong as the other three, but he's definitively just as dangerous as them.
    • Urogi's Blood Demon Art allows him to to generate and scream powerful sound waves from his mouth. When used, the power is so strong that it made Tanjiro bleed from both his nose and ears, stunning him momentarily. He can also use utilize the demon art with his flesh, as best seen when he uses his flesh to turn his severed leg into a mouth to scream waves at Tanjiro again. Just like Karaku, thanks to Urogi's thrill of battle, he's just as bad as his other fellow clones.
  • There's also his backstory that perfectly captures Hantengu's delusions: As a child, Hantengu was known for being a pathetic liar, always lying about something so he could have others "sympathize" with him. He took this lying path to a whole level of insanity, since through out most of his adult life, he often committed many heinous crimes such as theft and even murder, all while proclaiming himself to be an "innocent person", showing just how mentally unstable and delusional he was. Hantengu also married several times and had children, but due to believing he was "mistreated" by his family after being confronted for his deceptive nature, he would kill all of them in "retaliation". This shows that even as a human being, Hantengu was a huge scumbag who will kill anyone, even his own kin, just for confronting him for being who he truly is: A lying and delusional madman.
    • The scariest part about this is that Hantengu had lied so many times that he even forgot his own name. He's been lying for so long that he can't remember his real name, mainly because he kept creating fake identities to commit his atrocities. This showcases just how truly insane Hantengu was as a human.
• Chapter 111: Gyokko (Upper Moon 5) looks very unsettling, looking like a mixture of a humanoid figure with some fish parts, who lives inside of a ceramic pot and has the position of his eyes and mouth(s) exchanged, but the worst part of him is his twisted personality, being a Mad Artist who gets very upset if people don't appreciate his macabre "art". One of the most horrid examples is a "work of art" that he shows to Tokitou, showing several swordsmiths having their bodies stitched together in a terrifying fashion, with them still being alive after the process, as shown when Gyokko turns one of the stabbed swords causing them to scream in agony. If that is not enough, his main ability is the power to summon some strange demonic fish-like beings that look straight of a work of Junji Ito.
  • Gyokko uses his Blood Demon Art to imprison Muichiro in a water basin to suffocate. If not for his strong will and Kotetsu's heroic rescue, he would've slowly suffocated to death.
• Chapter 116: After finding the main body of Hantengu, Tanjiro uses his Hinokami Kagura to decapitate the cowardly demon. At first, it seems to go well. Until Tanjiro suddenly feels the presence of a demon, whose body is covered in shadows closing in on him, while he's trying to finish off Hantengu. The demon then uses his drum to summon wood dragons to attack Tanjiro, and the boy gets nearly killed, but was luckily saved by Nezuko. After getting to safe distance, Tanjiro and his group comes face-to-face with the sixth clone of Hantengu: Zohakuten, the personification of Hantengu's hatred, the four emotion clones fused into one. And the worst part is that he's also credited as Hantengu's strongest clone, meaning he's far more dangerous than his other four clones.
  • And how exactly did Zohakuten came to be? Well, it was because of Sekido, who fuses with Karaku, Urogi, and Aizetsu to become Zohakuten. The method of doing so? By FORCEFULLY absorbing them. Karaku's and Urogi's horrified expressions and Aizetsu attempting to protest further supports the fact Sekido fuses with his other three clones into Zohakuten without their consent.
    • What's more is that Sekido did all this with zero warning whatsoever.
  • Zohakuten in general is a terrifying demon to witness. He has the form of a child, and is clearly like Sekido, angered by those who dare hurt his main body's "weak self" and can give out a intense death glare that it paralyzes Tanjiro and his group in fear. And the worse part is that he has all of his four clones's abilities, possibly to a greater extent: Sekido's electricity, Karaku's gust of wind, Urogi's sonic scream, and Aizetsu's piercing blows of air, making him an even harder opponent than his other four clones.
  • As a side note, as Tanjiro is attempting to decapitate Hantengu, the latter lets out a horrific screech that sounds like a mixture of a raspy squeal and grinding metal.

• Chapter 125: While Mitsuri was holding off Zohakuten, Tanjiro, Nezuko, and Genya finds Hantengu's main body and Tanjiro goes once again to deliver the decapitation of the cowardly demon. However, to Tanjiro's (as well as the audience's) shock, Hantengu unexpectedly grows into a larger body and brutally chokes/smothers Tanjiro, all while screaming in rage that he's innocent and why Tanjiro couldn't see that. If it weren't for Genya and Nezuko, Tanjiro would slowly die a brutal death by the hands of Hantengu's giant clone that is Urami, the personification of Hantengu's resentment.

• Chapter 127: To further prove the overall strength and power of Zohakuten, it took Mitsuri to hold him off til Tanjiro, Nezuko, and Genya goes to find the main body of Hantengu. She did well at first, but she later got overwhelmed by Zohakuten's powerful scream. She later regains her strength as she finally awakens her Demon Slayer Mark to fight on equal grounds with the Hatred Demon. But later on, we see that despite Mitsuri's best efforts, she still couldn't take down the demon and was nearly killed, but luckily, thanks to death of Hantengu, Zohakuten was destroy. But it was very clear that if Tanjiro didn't kill Hantengu on time, then Mitsuri would've meet her end. This proves just how strong Zohakuten truly was.
• We later see Muzan back in his child form shortly after the deaths of Gyokko and Hantengu. His "mother" sees the mess he's made and so that means he is angry that two more Upper Ranks had been killed, right? Wrong! In fact, he is ecstatic because in his final moments, Hantengu had caught a glimpse of Nezuko in broad daylight. He kills both his "mother" and the maid who had entered the room, the latter being horrified at seeing the child grow into a man at rapid speed. Now that Nezuko has conquered the sun, Muzan's goal has changed. Instead of searching for the Blue Spider Lily, he decides to devour Nezuko so HE can become immune to the sun. His backstory explains how he had become a demon and his goals on creating a perfect demon.

Hashira Training Arc

• Muzan manages to find the Ubuyashiki estate. In order to kill him, Kagaya uses a bomb which engulfs Muzan, him, his wife Amane and their eldest daughters.
• Muzan survives the explosion, and his body afterwards is full on Body Horror, with his skin melted.

Dimensional Infinity Fortress Arc

• Doma was a monster long before he met Muzan and became a demon. When he was born, his parents assumed him to be a reincarnation of a god due to his white hair and rainbow-colored eyes and set him up to be the head of a scam cult that they started. The problem was that Doma was born a sociopath and he never believed in any of the cult's teachings or even an afterlife for that matter and believed that the people who came to him were insane. Just to show how emotionless he is, he learned from his mother that his father was having sex with female members of the cult so she killed him before killing herself but Doma responded by saying now he has to find someone to clean up the mess. And when he became a demon, he believed that by eating those who came to him, they will live forever inside him. Oh, and it turns out this guy is the reason Inosuke became an orphan. His mother, who had fled from an abusive marriage, wished to join the cult. But then she found out about Doma's true nature, so he ended up killing her to keep the secret safe. He's also the reason Shinobu's sister is dead, and his only regret is that he didn't eat her before the sun started to rise.
• Doma kills Shinobu by embracing her and absorbing her into his body.
• When Kanao points out to Doma that he's nothing but an empty shell incapable of feeling anything, that's when he stops smiling and decides to stop playing with her and Inosuke.
• As satisfying as it is to see him get his just desserts, it’s creepy to watch as Doma’s face melts off from the wisteria poison.
• Even when he's at death's door, Doma still is incapable of feeling any emotions. If anything, he's just disappointed.
  • And when Shinobu confronts him before passing on, in a disturbing display, Doma actually falls for her and asks her to accompany him to hell, as if asking her out on a date. And to makes worse, Word of God states that he spends his time in Hell telling the demons that Shinobu killed to forgive her, all the while continuing to justify his actions. This shows that even when loving someone, Doma still wouldn’t feel remorse for any of his actions, making redemption truly impossible for him.

Sunrise Countdown Arc

• Iguro's backstory: he spent his childhood kept in a cage by his mother and aunts, who worshiped a naga-like demon that had made them rich off the belongings of its victims. Why was young Iguro the only boy in the family? Because the demon also had a taste for infants, so his relatives had fed her their newborn sons; Iguro was just being raised to a certain age as a 'special' meal as a result of the demon's disturbing infatuation with his unusual eyes. She even ordered the women to cut his mouth to resemble hers (which is why he covers it with bandages) and drank the blood they collected during the process. His family did this gleefully, but he was so traumatized by it all that he has Survivor Guilt over the demon killing them when he escaped.
• Chapter 201: Muzan is finally dead but not before pulling one last act. Before he dies he places his remaining blood and strength into Tanjiro along with his memories, effectively turning Tanjiro into a copy of himself who immediately starts attacking the corps. And the worst part? He is immune to the sun now.
• Chapter 202: As Tanjiro gets worse, he starts sprouting tentacles made from his spine and shooting balls of energy out of his mouth. Nezuko manages to block his energy attacks with her bare hand and boy, the end result isn't pretty. Her hand is now a bloody mess and her fingernails are falling off!
  • Kanao is impaled through the chest while injecting Tanjiro with the last drug to turn demons back into human. Luckily, she gets better.
• Chapter 203: In his Mental World, it is revealed that Tanjiro was completely aware of the battle the whole time, but he was unable to stop Muzan, as he was trapped by the latter's cells. Then they both begin a Battle in the Center of the Mind, as despite Tanjiro' efforts to shrug off Muzan' temptations and lies, he was about to lose if it wasn't for the cure.
  • Muzan's final fate is to pathetically begging for his life while disappearing for good alone in the darkness of hell. Not that he didn't deserve it, though.