Kimetsu no Yaiba Chapter 191 Spoiler/Discussion Thread

[Admiral Teach]

Its not exactly a brain function issue considering that cutting a demon through its head does not kill them. So far its only the neck. Its also not a spine issue considering cutting a demons spine does not kill them either. The nichirin blades normally do something which kills demons when you decapitate them and red blades slow down their regeneration for a time. The only lore we have about this concerns nichirin blades being made from metal which bathes in the sun and whatnot... and red blades simply seem like a way to release more of saod energy considering how it is attained.

The actual thinking part of our "Brains" is the brain stem, which actually extends down right to where the demon slayers are cutting. If that gets chopped and can't regenerate, the demon can't regenerate. We have been shown the clear presence of the Soul. Meaning, when demons are dying and "thinking" it is as their spirit, not their flesh. The flesh is dying and dissolving to ash and then thin air because their thought process has ceased. And their thoughts, their emotions, have a critical affect on their entire being, and even something simple as an emotional shock will result in harsh consequinces, as seen with Kokushibou disintegrating after being revolted by his own repugnant visage. Therefore, Demons do need their brains to live, they need them to tether their emotional will to the physical plain, I believe. If they're emotionally resilient enough, they can last long enough before dissolving to regen the head, like with Akaza. If they just don't have that, like Douma, they die at once. And then some of them succeed in regenerating and then mentally screw themselves, like Koku.

With Muzan, he will never regret his existence. But his body still needs its will attached. The brain stem is, I'm assuming, the tether, the bridge between his soul and body. To ensure he isn't deteriorating while his original brain regenerates, he has multiple ones stashed all over.

Now, what really, really confuses me is the hearts. I'm guessing those are blood pumping mechanisms. Because so far the heart definitely had no relevance to the demon body. Destroying them did nothing. though maybe there's something else there that helps Muzan, perhaps for breaking into multiple miniature forms of himself, like he did with Yuirichi.

 

[kkck]

The actual thinking part of our "Brains" is the brain stem, which actually extends down right to where the demon slayers are cutting. If that gets chopped and can't regenerate, the demon can't regenerate. We have been shown the clear presence of the Soul. Meaning, when demons are dying and "thinking" it is as their spirit, not their flesh. The flesh is dying and dissolving to ash and then thin air because their thought process has ceased. And their thoughts, their emotions, have a critical affect on their entire being, and even something simple as an emotional shock will result in harsh consequinces, as seen with Kokushibou disintegrating after being revolted by his own repugnant visage. Therefore, Demons do need their brains to live, they need them to tether their emotional will to the physical plain, I believe. If they're emotionally resilient enough, they can last long enough before dissolving to regen the head, like with Akaza. If they just don't have that, like Douma, they die at once. And then some of them succeed in regenerating and then mentally screw themselves, like Koku.

With Muzan, he will never regret his existence. But his body still needs its will attached. The brain stem is, I'm assuming, the tether, the bridge between his soul and body. To ensure he isn't deteriorating while his original brain regenerates, he has multiple ones stashed all over.

Now, what really, really confuses me is the hearts. I'm guessing those are blood pumping mechanisms. Because so far the heart definitely had no relevance to the demon body. Destroying them did nothing. though maybe there's something else there that helps Muzan, perhaps for breaking into multiple miniature forms of himself, like he did with Yuirichi.

The issue would be that you can always find an exception to the effects of a demon being cut somehow or somewhere. As in, we have cases of demons surviving without brains and cases of demons surviving without heart. The most we have happens to demons when they get hurt in vital organs is that they get staggered and then they regenerate. I agree in that a demon's emotional state has a huge part to play here but in the end the brain or heart suddenly being that huge a weakness to muzan is a huge inconsistency in regards to lesser demons who had no such weakness. I'd be able to make sense of muzan's multiple brains allowing him to not get staggered from having several brains cut for instance but them along with the hearts being cut killing him is a massive weakness which no other demon has. As in, would you believe kokushibo can be killed if a hashira cuts through his heart and brain?

 

[Gallon]

The actual thinking part of our "Brains" is the brain stem, which actually extends down right to where the demon slayers are cutting. If that gets chopped and can't regenerate, the demon can't regenerate. We have been shown the clear presence of the Soul. Meaning, when demons are dying and "thinking" it is as their spirit, not their flesh. The flesh is dying and dissolving to ash and then thin air because their thought process has ceased. And their thoughts, their emotions, have a critical affect on their entire being, and even something simple as an emotional shock will result in harsh consequinces, as seen with Kokushibou disintegrating after being revolted by his own repugnant visage. Therefore, Demons do need their brains to live, they need them to tether their emotional will to the physical plain, I believe. If they're emotionally resilient enough, they can last long enough before dissolving to regen the head, like with Akaza. If they just don't have that, like Douma, they die at once. And then some of them succeed in regenerating and then mentally screw themselves, like Koku.

With Muzan, he will never regret his existence. But his body still needs its will attached. The brain stem is, I'm assuming, the tether, the bridge between his soul and body. To ensure he isn't deteriorating while his original brain regenerates, he has multiple ones stashed all over.

Now, what really, really confuses me is the hearts. I'm guessing those are blood pumping mechanisms. Because so far the heart definitely had no relevance to the demon body. Destroying them did nothing. though maybe there's something else there that helps Muzan, perhaps for breaking into multiple miniature forms of himself, like he did with Yuirichi.

The brainstem is not really involved in thinking, and the demon slayers usually cut farther down, somewhere in the cervical portions of the spinal cord. I would've liked an explanation like this if demons could be killed through trauma to their central nervous system, but it's only possible with Nichirin blades, so it's hardly scientific.
Muzan needs to have his hearts destroyed in order to halt his regeneration as well, so it's more of a "cool" and quirky explanation than a medical or anatomical one, to be fair.

 

[Sato-san]

The extra hearts are, as you said just extra organs for faster pumping of blood. That’s probably how Demons in general regenerate and that’s probably what makes his regeneration so much faster than all the other Demons. Either that, or those are the organs of Demons he’s absorbed. Maybe he has a limit to how many Demons he can absorb

 

[Meliodaf]

I love this! This is exactly what I wanted. For everyone to get their moment before Tanjiro finally gets to get his revenge and beat Muzan to death. There are a lot of edgelord characters in anime who wish they could hate like Tanjiro does. He refuses to even let go of his sword while unconscious and practically dead because he’s that determined to kill Muzan. Destroyed face and all, Tanjiro is awesome. I hope this moment is as good as I expect it to be because I’ve been waiting for it since Tanjiro met him in Asakusa.

And is that Giyuu missing an arm?

 

[levi12]

I hope Tanjiro is gonna kill Muzan with 13 form and then kill him with dotg just like Yoriichi did.

Question all pillars are out and two main duo and Kanao won t being joining either.

Tanjiro needs very big power boost. As Muzan is far more powerful than All upper moons.

I am pretty sure Tanjiro can do it.

I don t think any of pillars and main duo of zen and inosuke is dead just knock out. This just to show how powerful Muzan is.

This is all big set up for Tanjiro vs Muzan.

I hope all Pillars and Kanao and Tanjiro all survive this

 

[Meliodaf]

I hope Tanjiro is gonna kill Muzan with 13 form and then kill him with dotg just like Yoriichi did.

Question all pillars are out and two main duo and Kanao won t being joining either.

Tanjiro needs very big power boost. As Muzan is far more powerful than All upper moons.

I am pretty sure Tanjiro can do it.

I don t think any of pillars and main duo of zen and inosuke is dead just knock out. This just to show how powerful Muzan is.

This is all big set up for Tanjiro vs Muzan.

I hope all Pillars and Kanao and Tanjiro all survive this

Himejima will almost certainly be dead by the end of this. Maybe Iguro and Sanemi too.

 

[levi12]

Himejima will almost certainly be dead by the end of this. Maybe Iguro and Sanemi too.

Possible I hope all pillars survive though.