Kyogai - Tumblr Posts

no extra today lol soz 🙏 but here is a tiny lil training/adventure montage for tanjiro (and nezuko who is off-screen haha) while hakuji-sensei tries to put soyama soryuu on hiatus so he can help the kamados. next time: hakuji goes to find the kamado sibs!

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How Does Eating Humans Work?

Hello, Gotou here. We’re shamelessly borrowing from the format of a KnY Fanbook #2 comic to launch an investigation into demon metabolism and development by crossing the Sanzu River again to interview demons in the underworld. While we’ll be using canon materials as a base, the analysis and conjecture herein is personal, so we ask for your understanding. Also, please note that consuming any food in the underworld will make you unable to return, and we cannot promise your safety even though the interview subjects are dead, so please come along at your own risk.

Some of the questions we’d like to answer are, why do demons need to eat humans? How much do they need to eat to survive? Are there factors that influence how eating humans makes them stronger? If they don’t want to kill humans, what are their other options? We’ve rounded up some special guests below the cut (hidden for length and grossness), everyone from the lowly Temple Demon to the lovely Tamayo, to see what their actions in canon might tell us.

First, a review of what canon tells us, mostly as summarized in Fanbook #2: 1. With one exception named Yushirou, all demons were created by Kibutsuji Muzan, for his own purposes. They all have some amount of his blood, and can be divided into four classes depending on how powerful they are. From top to bottom, the Upper Moons, the Lower Moons, demons with special abilities, and other demons without any special characteristics. 2. Demons may be stronger depending on how much of Kibutsuji Muzan’s blood they have. Most beings’ cannot handle a large amount of his blood, and it will rupture the cells and that being will die, but there are demons who adapt well to it. 3. Typically, sunlight is the only way to kill a demon, by either bathing them in sunlight or cutting of their head with a Nichirin blade. However, there are powerful demons for whom chopping off their head does not work, and if it’s strong enough, demons can also be killed by wisteria poison.

4. Demons eat human blood and flesh. The more they eat, the stronger they become, and the faster their regenerative abilities become. Some humans have “Marechi,” a rare blood type, which is especially nutritious to demons, and eating one Marechi is the equivalent of eating several humans.

That’s an interesting thing we’d like to come back to, especially since we’re looking for quantitative information about how demons gain nutrition (though I have my doubts we'll get enough for statistical analysis). As an interesting note, Fanbook #2 also tells us that if demons try to consume the same edibles humans do, they’ll vomit it back up.

I’m told that Miss Tamayo drinks tea, though. That’ll be an interesting question for later. In my notes, it seems she’s also explained to Tanjirou back in Chapter 15 that demons will normally go berserk if they go a long time without consuming any blood or flesh. Berserk is one thing, but I wonder if they can starve to death? We’ll see if these canon clues will lead us to anything. We’ll begin now in an interview format. Hopefully this will go smoothly, but I’ve got a feeling it won’t. First up, we’ve the Temple Demon.

Temple: Who were you calling ‘lowly’ just now? Up there, above the cut?

Gotou: That was in a literal sense, not having Blood Techniques means you’re in the bottom common tier of demons.

Temple: Argh. Fine. What do you want to know?

Gotou: In Chapter 2, you were spotted with three human victims. However, it seems you left their bodies mostly intact and only ate small parts instead of consuming one full human at a time. Could you comment on this?

Temple: I’d have gotten to more later if that whelp with the strong legs didn’t interrupt me! Who’s got time to eat entire humans anyway? I went for the easy stuff first.

Gotou: I see. It appears you might had focused on key organs, like the heart and the liver. Would you say these are especially nutritionally dense?

Temple: I guess. If I’m going to eat humans, I’m going to start with what’s worth bothering to digest. Blood’s easier on the stomach, so that’s what I was busy with on the lady there.

Gotou: Then it takes effort to digest? Hmm. Let’s come back to this later. How many humans would you say you consumed, including these three?

Temple: Not a lot… I tried to get a variety so I could get stronger faster, but…

Gotou: I’ll put down a guess as ten or less. Let’s move on to someone who has a sharper memory for numbers. One of our longer-lived guests at Mt. Fujikasane for 47 years, the Hand Demon. While most of the demons on the mountain had only eaten two or three humans, you’ve eaten a whole 50 of the children who headed into the Final Selection, didn’t you?

Hand: Yes, that’s right. It was hard at first since I wasn’t very strong, and the demons usually all went crazy there eating each other, just like that one brat who got away in Chapter 7 said. If you could manage to kill any of the kids, you had the other demons to fight off to even get a piece to yourself. That was enough to get me by, and stronger, little by little. Your body learns to make your meals last, and make the most of what you can get. I usually only had a bite of one child a year, can you imagine how horrible that was? Most demons who survive usually figure out some way to develop and survive better, and once my cells found something that worked for me, I kept doing it. I got really good at snatching away prey from other demons, and soon enough I was a bigger threat than any of them. None of them could, you might say, lay a hand on me.

Gotou: That’s an interesting point about self-development. A demon named Nezuko was spent two years doing that in her sleep.

Hand: She must have had a big meal before that!

Gotou: Well, anyway. It seems that in near starving conditions, your metabolism made the most of what you had, leading to the most efficient use of whatever food was available to you.

Hand: That’s right, I got really good at it. Wasn’t always pretty, but I made it work. I got to a point where I could go two years without eating and still keep my wits about me while the other demons were going mad. But I chose to eat. I liked to keep my appetite for specific children.

Gotou: That smile is not reassuring. Some humans taste better than others, I guess?

Hand: That’s for sure. This one kid tasted awful, like rust and man sweat! I still don’t have that disgusting taste out of my mouth! But he was one of my more satisfying meals, so I ate more of him.

Gotou: Then why would you… nevermind, I don’t like that smile, no further questions. While I had hoped to keep these interviews focused on quantities of humans consumed, it does seem personal taste is worth asking about. I had tried to invite a Swamp Demon from Chapter 11, but it kept arguing with itself and it felt like I’d be wasting my time. The one definite thing I learned was that this demon is picky, with a distinct preference for 16-year-old girls. Based on the number of trinkets he kept, it seems he had consumed at least seventeen of them, including several in one town. Sheesh, that’s sort of a rough mission to send a first-timer on. I’ve got a more cooperative guest here to discuss her tastes, a Snake Demon who, according to Chapter 188, has a special taste for baby flesh.

Snake: Thank you for having me here. It’s good to be appreciated again.

Gotou: Did you only eat babies?

Snake: Goodness, no. Babies are delicious, but they aren’t very nutritious. And their skulls certainly aren’t that big, the ones I lounged around with were from the people whom I killed and stole from. But you know the nice thing about baby skulls? They’re still soft. They take a long time to digest, but I can swallow them whole.

Gotou: Like… like a snake, then. Sorry, I’m a little ill hearing that. Let’s back up, were all those skulls the remains of adults you ate, then?

Snake: Meh, I ate some of them of better-looking ones, but most of them I only killed. I could usually kill a lot more at a time than I could bother eating, my killing record was fifty women all at once.

Gotou: And you didn’t find that wasteful?

Snake: Wasteful? Not at all. I wasn’t exactly in dire straits, I lived a more luxurious life than most demons do. That meant I could afford to wait for a truly delicious meal, like how you humans might leave something in a slow-cooker to enjoy the perfect combination of doneness and tenderness, plated in the most appetizing of ways.

Gotou: I guess demons and humans are similar in that regard.

Snake: I’m so glad you can relate! Then you understand the frustration of a meal you’ve be preparing for years opening up the slow-cooker and running away right when they were just about done.

Gotou: I have never had that experience.

Snake: I’ll get you, my pretty. And your little snake, too.

Gotou: I think we might have gotten a little off-topic here. It does seem digesting humans comes with some difficulty. I’d like to invite the Drum Demon in next. Your name is Kyougai, I hear?

Kyougai: !!

Gotou: Kyogai, right?

Kyougai: You’ve heard of me! You know my name!

Gotou: I happened to, yes.

Kyougai: What have you heard???

Gotou: That you were kicked out of the Lower Moons for being unable to consume enough humans.

Kyougai: Oh. ……..yeah, that’s me.

Gotou: I thought demons go berserk if they go a long time without consuming humans. Wouldn’t that make an inability to consume them problematic?

Kyougai: It wasn’t that I couldn’t eat them! Like I said in Chapter 24, I had to in order to sustain myself, just like any other demon. But, at some point, I couldn’t eat as much as I used to. That happens to humans too, doesn’t it? When you just can’t stomach anymore?

Gotou: You mean like when you’ve overeaten? In a human’s case that feeling may go away within a few hours.

Kyougai: Sort of like that, but you know, humans reach a time when nothing is appetizing or the thought of eating makes them feel sick, right? Isn’t that the human condition?

Gotou: …uh… maybe if they have a medical condition? Or anxiety? Do demons get anxiety? Or eating disorders?

Kyougai: I… I don’t know. I just wasn’t good enough.

Gotou: I think it’s plenty good if you stopped eating humans. Though to have developed Blood Techniques and been a Lower Moon in the first place, you must had eaten a great number of them.

Kyougai: You think I’m great?

Gotou: What?

Kyougai: No, sorry, I was getting ahead of myself. It’s true, I used to be able to eat as many as the other Lower Moons always consumed. Our stomachs were stronger, you might say. Demons got strong by eating humans, and then the more you did that the better you usually got at it, so the strong ones would eat more and more and keep getting stronger and stronger. At least, that’s how it usually worked. I’ve seen other demons below me reached that point too, where they feel the drive to eat, but then they have trouble digesting it for a long time, so they don’t wind up eating that many people.

Gotou: Then it would make sense to eat the most nutritionally dense parts first.

Kyougai: Or a Marechi.

Gotou: Yes, or a Marechi.

Kyougai: It was a great idea, wasn’t it?

Gotou: I cannot condone any consumption of humans as a good idea.

Kyougai: I knew it. I’m nothing. Go ahead, stomp all over everything I ever tried to accomplish.

Gotou: I think I’m going to move on to my next interviewee now. It looks like we’ve got… oh, would you look at this? Lower Moon One. Enmu, I believe.

Enmu: You can believe whatever you want. I’m happy to help.

Gotou: I don’t need any help, thanks. I’m curious, since you were one of the stronger demons out there, it seems you had a stronger capacity for consuming humans.

Enmu: I did, I was always careful and paced myself so the Demon Slayers wouldn’t notice me. I took my time. I liked to enjoy e-e-e-a-c-h one.

Gotou: Then you had tastes too? Like babies, or 16-year-old girls?

Enmu: I could season any human to my liking. They’re all very easy to prepare.

Gotou: I’m still trying to get quantitative data. Can you tell me at least a rough estimate of how many humans you consumed?

Enmu: I told this more precisely to that boy with the earrings back in Chapter 59, and I can tell you this too. At my best, I could had eaten over two-hundred people at once if I took my time.

Gotou: OH MY GAW----sorry, I dropped my pen. Two hundred, at once?

Enmu: Yes. If I had just. Had. A little. More. Time.

Gotou: Clearly there is a huge difference between what common demons are capable of and what the Twelve Moons are capable of.

Daki: Psh, those were all any random common people. That’s nothing to brag about.

Gotou: Excuse me, and you are?

Daki: Daki, Upper Moon Six. You want something really impressive, you talk to the Upper Moons.

Gotou: I’m sorry, I don’t see you on my list.

Daki: What! Your list is stupid. Look me in the eyes, I’m Upper Moon Six!

Gotou: Very well, then. What can you tell me about your diet, Miss Upper Moon Six?

Daki: That’s more like it. It’s true that digestion takes a while, and takes some effort. Even though we Upper Moons may have eaten hundreds of people in our lifetimes, it’s not as if we gorge ourselves. The clever ones among us save prey for later to eat when we feel ready for it.

Gotou: Food storage? How do you keep them fresh?

Daki: You leave them still alive, numbskull. Nobody wants to eat something cold, that’s gross.

Gotou: I see, so that’s why demons prefer to go after new kills instead of saving what they’ve already managed to kill. That also might explain why the demons on Mt. Fujikasane wouldn’t had eaten many humans, if they found long dead ones in edible.

Daki: You want to know the real secret to eating humans? You can eat what you find tastes good, sure. But to get stronger, you eat strong people. Like your Corp members, the ones besides chumps like you? Using all that Breath makes their muscles really lean and potent, it’s like they come offering themselves as protein bars for us.

Gotou: You make them sound like a fad diet…

Daki: The real secret is eating Pillars. Besides Marechi, they’re the strongest meals out there. Guess how many I’ve eaten?

Gotou: I don’t have the data to make an educated guess.

Daki: Then get educated! Look back at Chapter 88! I’ve eaten seven Pillars, and my brother has eaten fifteen!

Gotou: Your brother? Who is he, then, Upper Moon Five?

Daki: What? Ew. Gross. Gross! No way, ew!

Gotou: Hmm… eating Pillars, huh? Well, I can think of one Pillar who was…

Douma: Me too!

Gotou: Speak of the devil.

Douma: Actually, we Upper Moons can! And he's not Satan, that's not how this works. But I guess Muzan-sama’s curse doesn’t effect us now. Ask me anything you want!

Gotou: That Chapter 143 reference was such a rude entrance. I understand that Pillars are particularly nutritious—

Douma: Oh, please don’t misunderstand! I don’t even eat all the Pillars I’ve encountered. There was the one Flower Pillar who got away from me, but some of the boy pillars I just leave around. What’s really the key to consistent nutritional intake is women! It’s really unhealthy for a demon not to get enough women in their diet, that’s why even if you’re only looking for Marechi or Pillars, your metabolism is going to get thrown out of whack with sudden big meals. You grow a stronger metabolism with consistency, I believe!

Gotou: If I could stop you there, I had an image from Chapter 142 I preferred to focus on for this case study. I see you keep a wide collection of skulls, from victims whom I assume you ate.

Douma: Yes, they all stayed together inside me for eternity, but the room looked lonely without décor.

Gotou: It seems other demons usually go for nutritionally dense organs like hearts or livers, or easy to digest parts of the body, perhaps just blood sometimes. Eating the entire victim, bones and all, doesn’t seem to be the norm.

Douma: Bones are organs too, you know! That’s where blood is made, at its freshest. They do take more practice in learning to digest, and I had to find a way around not having to chew them, but the bone marrow is very, very good for you, so I make sure to consume it frequently. It may take more time and it causes some of my followers to panic more while they wait, though, that’s a bit of a downside. Oh, and I guess bones can make good storage for some sneaky poison. Even fingernails and hair follicles, who’d have thought?

Gotou: I don’t think hair would have much nutritional value in the first place. In all my years, I can never recall seeing a victim with their hair eaten.

Douma: Tsk, tsk! Clearly you haven’t done much metabolism research in advance. I was really impressed by how well Shinobu-chan understood how my digestion would work. Eating hair can do amazing things! Isn’t that right, Genya-kun?

Genya: ?????????

Gotou: Genya-kun!?

Genya: What am I doing here?

Gotou: I don’t think you’re supposed to be here. Isn’t there, you know, another side? The other direction?

Genya: What are you doing here? Did you die?

Gotou: I’m here doing research on demon metabolism and how they get stronger by consuming flesh.

Douma: What can you tell us about what up with having your friend feed you hair you found on the floor in Chapters 170-171, Genya-kun?

Genya: I’m not a demon!! Why the hell are you asking me?

Douma: ‘Hell’! Haha, good one!

Gotou: How do you even know about that? You were dead almost a full volume before that. And Genya’s different, he’s not a case study in how demons consuming humans works!

Douma: Are you certain?

Gotou: I hear the term get thrown around a lot that he’s ‘half-demon’, but—

Genya: I’m not a demon!!!

Gotou: --how would that even work? That would imply that one of his parents had to be a demon, and that—

Genya: What did you say about my mother!?!

Gotou: What? Nothing—

Genya: You say that to my face! You just trying saying something about my mother to my face! My mother never actually ate any flesh, you got that? She doesn’t deserve any of this!

Gotou: Genya, calm down, what—

Douma: I see we’re learning nothing about hair at all. Maybe Kokushibou-dono would provide better commentary on that?

Genya: Mom? Mo-o-o-o-m? Are you down here somewhere?

Gotou: And there he goes… wait, did you say Kokushibou? Upper Moon One? Oh no—he—he didn’t want me bothering him, he did not agree to another interview—

Douma: He-e-e-e-e-y, Kokushibou-dono! How did that work with Genya-kun eating your hair? Hair can be nutritious, right?

Kokushibou: You would gain… nothing… from consuming human hair… it’s not… flesh… you wasted your energy digesting it…

Douma: Aww, cutting it off them would had been sad, though.

Kokushibou: Demon hair… like demon weapons… is made… from our unique cells. It’s not dead… like human locks. Because that boy ate my live cells… it affected him…

Gotou: Yes, because he had a very, very unique metabolism, analyzed separately in this post. To be perfectly clear, Genya is completely human with cells that could temporarily transform, and he never consumed human flesh.

Kokushibou: He… vexes me…

Gotou: Um… while I’ve got you here, you’re one of the longest lived demons, clocking in at over three, maybe four centuries. Do you have any estimate of how many humans you’ve consumed?

Kokushibou: ……I see in… Chapter 100… that you are 23 years old?

Gotou: That is correct.

Kokushibou: Do you bother… remembering how many meals… you’ve had in a mere 23 years?

Gotou: I’m very sorry to have bothered you.

Douma: Kokushibou-dono’s ancient compared to the rest of us! But if I tried, I could probably recall. Let’s see. One, two, three, four…

Gotou: Is that? Your finger in your brain? Oh—ohhh—that is disgusting---I really don’t need to know numbers that badly, please stop. Is there maybe just some average you can give me for the Upper Moons instead? Like how many you’d eat in a month?

Douma: I wish I could, but a certain someone was an annoying outlier and didn’t like to eat so many humans. He made me worry all the time about his health.

Gotou: Really? Who might that be?

Douma: Hello-o-o-o-o-? Akaza-dono? Yoohoo! He spends all his time with his wife now and never answers when I call, it makes me so sad. Akaza-dono did eat humans, plenty of strong ones, but any time he wasn’t under orders from Muzan he liked to spend his time training instead of eating. Fanbook #1 says he did that way more than eating!

Gotou: Training? What sort of training?

Douma: Similar things to what your Corp members did, I imagine. Doing squats, throwing punches, things like that.

Gotou: Then demon muscles had similar function to human muscles, and could be strengthened through hard work? That’s surprising.

Douma: I know, right? I’ll let you in on a secret, I don’t think it was the physically repetition that did anything. I think it was his willpower getting honed and shaping his muscles.

Douma: I had to focus when I acquired new skills too, like breaking down poisons. A lot of sad, lowly demons, like that Hand Demon fellow? They focus as hard as they can in their desperation, or focus on some strong emotion or attachment or whatever, and they grow and develop because of it. Sometimes all their weak bodies can manage is an ugly mutation, but that’s proof enough of how much focus they had.

Gotou: That sheds a lot of light on Nezuko, actually.

Douma: Shed “light” on Nezuko-chan, hahaha! Sunlight! You humans are all so witty!

Gotou: Speaking of willpower, I’ve got one more interview I need to get to down here. Of all the demons I have records of, only Nezuko went her whole time as a demon without consuming any human flesh, although she did go through moments of berserk cravings for it. It’s possible that other demons were killed before they could consume anything, but typically they will consume flesh as soon as possible, which is why its common for their family and close relations to be among the first ones killed. Tomioka-san even mentioned in Chapter 1 that these close relations are especially nutritious.

Gotou: A demon about as old as Kokushibou, if not older, is a special case of her own. She was one of the only demons we know of to have escaped Kibutsuji’s curse and acted in dependently of him, including having created a demon of her own after two hundred years of trying. Most notably to our purposes, she trained herself to subsist on small amounts of blood, after having survived on corpses and wild animals for a time, according to the extensive Taisho Secrets at the end of Volume 21.

Tamayo: I explained this in more detail to Tanjirou-san in Chapter 15, but I went on to purchase blood from poor people, and extracted it in ways that wouldn’t be harmful to them. The one demon I created, Yushirou, could subsist on even less. I gained enough self-control that I could treat injured humans without feeling tempted into a berserk state.

Gotou: I was just talking to Douma about willpower making demons capable of accomplishing new physical developments. Was that how you were able to gain this state? I heard you even enjoy a cup of tea now and then.

Tamayo: Yes, I’ve taken a liking to it. I’d offer you some if not for this, you know, being hell. It’s nothing like the hell I went through when first resisting consuming humans, though. My demon body refused to take anything but fresh human flesh at first, but in the hardest moments, I always remembered a kind demon hunter who said he believed in me and my desire to defeat Kibutsuji Muzan. I believe Nezuko may have summoned her strength to resist the call of her demon cells in a similar way; she knew she had her brother there to rely on. Once she mastered something as remarkable as resisting the need for human flesh, it gave her the freedom to prioritize other developments.

Gotou: You spent centuries researching demon cells, especially how demons may break down and metabolize poisons.

Tamayo: I had not studied the metabolism of poisons until working with Shinobu-san. The medicine we concocted for Kibutsuji was only possible thanks to her work, and I couldn’t had worked with many of those wisteria-based substances on my own. I feel I was only there to fill in the gaps of her brilliant understanding.

Gotou: You’re very humble. I would pass along my thanks and compliments to Shinobu-sama too, but I’m pretty sure she’s not down here. On that note, did Genya-kun go back home?

Tamayo: He did after a nice reunion with his mother just now, it was very sweet. Shizu-san and I get along well, after all, we both carry similar guilt.

Gotou: Wait, was his mother a demon? That means Wind-sama’s mother was too? Wait?? What??

Tamayo: The worst hell I went through, or that any demon has gone through, is to realize what you’ve eaten after the hunger-driven madness clears. Being similar to your own cells, they’re easy on a volatile new anatomy to break down and digest. That’s why many demons may have driven themselves to forget everything all over again, or to twist their personalities to justify the horror, saying that because they ate the hearts of their loved ones and because demon flesh can live forever, then they never truly killed them. The truth always remained untwisted for me, and to this day, it torments me more than anything in this underworld can try.

Gotou: …

Tamayo: You should wake up now, Gotou. You’ve been through a lot; the nightmares must be taxing on your health. Please remember to eat well.

My latest addition to the Pocket World lineup, Infinite Arc! This piece can be viewed right-side up or upside-down! Enjoy fun times with all the demon slayers hanging out at the Ubuyashiki manor, or flip it and check out what Muzan's been up to with all his demon lackeys.

Which side do you prefer? Slayers or Demons?

I'm very proud of this piece and hope you all enjoy it too.

I really love this detail of Tanjiro asking for Kyogai's name, which doesn't happen in the manga. It ties into Kyogai's core desire really well.

Kyogai never wanted to be the greatest, or thought he was particularly. He had a limit to his ability, but everybody does. It was his fatal flaw that he placed his self-worth in the hands of others, even if they are toxic, like Muzan and the man in his flashback were among them. For whatever reason, possibly from being browbeaten for so long (by the man), Kyogai simply could not believe in himself without approval, and he threw away the last shred of his humanity to get it.

Kyogai, deep down, wanted his personal achievements to be recognised for what they were, rather than what they could be in the minds of sadistic editors or genocidal demon lords. They may not have been the greatest, but they were skills that had been honed by hard work and sheer willpower (Kyogai was almost certainly a demon at the time when he killed the man in his flashback - he was still trying to please this guy!), and the results were far better than either of the above would give credit for (his demon art, at least).

Tanjiro asking for his name compounds Kyogai's greatest desire - to be valued as an individual. It stumps him, because it's the last thing he expected. And no wonder - in the flashback, the man exclusively refers to Kyogai as 'you', like he's so unworthy even his name is beneath acknowledgement.

That's why it feels so much more personal and heavy when Tanjiro praises his demon art later, telling him 'Kyogai, this thing you worked hard at is really amazing'.