YKK Forum

My Theory of the YKK World

This was first posted on Cafe Alpha, I now post this here in hope to spark some discussions/debates:

After reading through all the manga volumes, I've come up with a theory with could explain most of the mysteries of the YKK World. I'd like to share it will all of you and see if it make sense to you.

The Past:

I believe that some single or series of catastrophic event(s) happened. This is either natural (likely) or man-made disaster. We know these things had happened:

1. Sea-level has risen dramatically
2. Eruption of Mt. Fuji
3. Sharp rise of radiation level

The timing of this event is most likely before the lifetime of Sensei since we saw in her youth the desolation of her world. We also know that Sensei is not involved in the development of robot series A1-A6. My guess is that this event(s) happened 200-300 years ago in the past.

The Result of the Catastrophic Events:

Here's some things which we saw in the manga which could be the result of the catastrophes happened 2-300 years ago:

Plant life grows abnormally. This may due to rising radiation levels.

Land animal (warm-blood animals) seemed to have disappeared or reduced in number (lack of land wildlife/birds, etc.)

Human population only fraction of its former size, and cities/towns disappearing over time

Robots or artificial humanoid life-forms, now part of human society.

Current human population consisted of mainly older people, with relatively fewer young adults or children.

Standard of living seemed to be somewhat maintained, but society itself is reverting back to one that's low-tech and agriculturally-based (automobile and use of gasoline increasing rare); big cities have become small towns.

Some key utilities were being maintained (power and water), while larger and less essential public infrastructures such as roads deteriorated. Telecommunication infrastructures (land line, cell phones), however, were no longer in operation. Only the Postal system remained.

Japan (and maybe other nation) were broken down into smaller nation-states which no apparent problem co-existing. The nation of Japan as we know it was gone.

Children were mainly home schooled, and their number seemed very small compared to adults

Temperature seemed to be on the rise, while snowing had become a rare phenomenon

The Sea level is continuing to rise

Nature, via vegetation, is creating some strange new life-forms which is similar to man-made creations or human being themselves.

Here's my Theory:

A catastrophe or a series of catastrophic events resulted in large-scale global-warming, melting of the poles and the rise of sea-level, the eruption of Mt. Fuji, and a sharp rise in surface radiation level. Most of the human population died in the catastrophe(s). After a few years, the survivors began to realize the most devastating effect of these events: human fertility rate started to drop dramatically. Scientist worked in earnest to find solution to this or mankind would face extinction.

After a while the survivors formed their own local city-states (at least in Japan), since travel has become difficult due to the sinking of most major coastal cities. Basic necessities of a civilization, such as water/electricity, have been maintained, while modern means of transportation were still in wide use. Commerce and factories continued to operate to whatever capacity they could afford. However, mankind still couldn't resolve the issue of declining birth rate. A group of scientists, believing that humanity was ultimately doomed to extinction, began to build robots which resembled human as much as possible in order to preserve human culture and society.

The Robots:

A series of robots, A1-A6, were developed to accomplish the goal of cultural preservation, and finally near-perfection was reached in the A7 series. Robots were designed live on this post-apocalyptic Earth unfriendly to human beings. They’re self-healing, impervious to human diseases, and more or less immortal. They’re also designed to be sustained via organic means of carbohydrate and/or fat consumption. Due to the lack of surviving land-based animal species, robots were designed so that they did not require protein and only need very little carbohydrate to survive. The goal of the robotic design after the catastrophe was probably to produce robots which can be considered human “replicants”; artificial beings which could function at any level of human society. As human population declined, some robots were build in order to maintain or replace the deteriorating public infrastructure due to the declining numbers of qualified workers (Kokone), while others robots were created in order to be scientist, artist, or other contributing members of the future human-like robotic society (Maruko, Alpha, Director Alpha).

About the Tappon:

Time passes, and about the time when the A7 was introduced, a group of scientists developed a large airplane/ship designed to fly indefinitely in the stratosphere in hope to escape the effect of radiation and restore the human fertility rate for those aboard. However, their efforts, after a lengthy amount of time (60-100 years, perhaps), has proven fruitless as they’ve failed to maintain or increase their own population size. Director Alpha, the first A7 robot, was probably brought on board to help with the research. She would ultimately be the only living being left alive on this special ship.

The Misago:

For some reason all records of A1-A6 were destroyed. The "Misago", a possible A2 model, was probably discarded when she did not display proper human behavior (anti-social, lack of notion of modesty, no speech capability). She's not destroyed like the other models may due to the fact that she was basically harmless, or some other reason yet to be told. I believe that the Misago (and most robots) liked children because somehow she knew that if there are more children in this world, robots would not have behave like human in order to be considered “perfect”, and robots similar to herself could exist for their own sake. Like to Kokone's dream of being her own self, I believe robots longed for a world which they didn’t to emulate human behavior or bear the burden of being "humanity's children". About why she ate fish: Since fish is the probably the most abundant form of available protein, she's probably designed to consume fish for sustenance. However that idea was flawed as that would require all robots to live near a major source of fish, and this robotic society therefore wouldn’t be a good emulation of the past human society. Future models were more advanced, requiring only simple carbohydrates to survive.

Alpha's Origin:

A scientist whom Alpha called "Owner" finally perfected the robotic human emulation when he built an A7M1 model called "Alpha". This is the first robot which believe in its own inherit humanity and generates true human emotions and behavior. The "Owner" decided to leave Alpha in order to function and learn on her own under the watchful eyes of his old friends, Sensei and Ojiisan. The purpose of this decision was to give Alpha the opportunity to learn how to function independently (of human and other robots), and to develop her own interactions and memories about other human and robots. Another purpose for her was added when the Owner sent Alpha a camera; she would also now record vivid memories of the people around her so that their lives would live through her in eternity. She also has the special ability to merge with other robots or machinery; either share other's sensory experiences or share them with other robots. She couldn’t ingest protein, but that maybe due to the initial design goal of sustenance via small amounts of carbohydrate/fat consumption. Aside from her artificial parts, she is ultimately human in her spirit. Maybe that’s why she’s also called Alpha; she’s not the first of her kind like Director Alpha, but she is first truly human robot. Only with the existence of Alpha, however, can the effort to preserve humanity considered a success

The Children, Taka and Makki:

The children might or might not be the blood relatives of Ojisan. They’re most likely not actual brothers and sisters. They’re probably children from other members of the village and for some reason (maybe their death) has decided that Ojisan was the best person to raise them both together. School was no longer needed since they are the only 2 young kids in the area. I believe that it’s also possible that they came from TEST TUBE research, which meant that they actually did not have biological parents, but may be born from the efforts of people like Sensei, as natural conception no longer occurred. I believed also that in YKK's world the notion of mother and father has been lost, instead the children sees all elders as their "parent" as no one is actually born naturally from of a parental pair anymore.


He's a former test-tube baby who's left the area to explore the world and to find work. He knows owner/sensei well. I believe he's on a quest of some sort with purpose not yet revealed. He might be doing work for Owner.

Robot/Human co-existence:

I believed that the earlier robot models weren't welcomed by the human population. That's the reason why they were all trained on self-defense and equipped with a non-lethal defensive weapon. Maybe the main reason for the destruction of A1-A6’s records was to erase negative memories of past robot-human relationships so the A7's wouldn't know how badly their ancestors were treated (and might decide to NOT to be humanity's children afterwards). But how come the co-existence is so peaceful now? I believe there’re 3 main reasons:

1. The A7 series robots were so human-like, that people accepted them better.
2. People now realized that extinction was a harsh reality, and that robots did represent the future of humanity. I believe that Robots may now be treasured all surviving humanity.
3. They NEEDED robots. Robots were the guardians of this decimated society, providing many of the essential social services. They probably kept the utilities and the good-producing factories running as well.

I think I may have more things to say about YKK, but I would welcome any kind of correction/debate/confirmation about this theory. I think it explained a lot when I first though it up, but I actually have confirmation by Kodansha about the theme of YKK. A description found on their webiste actually says: "In a world of fewer human beings with no major industry, mankind faces extinction. "

- Jeffrey Chen
Tuesday, August 5, 2003

It seems from the current manga that the A1-A6 were the records and sensations that humans value the most. For instance, there is a lot where Kokone is listening to the early A? records. Possibly the later A series were sensoriums recorded off humans directly (see below).

Then, when Sensei is piloting the Misago in her youth, this again was in order to record the experience of going beyond human limits, it seems she has a neural connection in her mouth to record the experience (anyone else see that? Or am I mistaken?)

There are also references by Sensei to the 3 prototypes before the A7M3's, so we can surmise that Alpha is one, Director Alpha is another, and possibly the Misago (it seems to fit descriptions given, except for her protein assimilation capability that Alpha lacks).

In addition Sensei seems to be constantly surprised that Alpha is the way she is (ie, when she obtained the keychain), in the translation it appears as though Sensei was hoping to find the key to true human-like robots, failed for quite a while, then despite all odds, the first prototype Alpha series "managed" it without too much human intervention; hence, she does not quite understand how it works. It is probably a genetic algorithm or something similar, where it evolves to work.

Considering how 'peaceful' YKK is now, it is possible there was a backlash to the first generation of robots (ie, Nai's reference to the male gender being 'weak', presumably many were killed off through abuse, neglect, hatred?) while the female ones were allowed to continue on (given that people thought they weren't a threat). Meanwhile, since a good 30+ years have passed, most people would have become accustomed to seeing them and wouldn't think twice about them (just look at kids and the Internet now!)

Interesting reading, overall...

- PC
Wednesday, August 6, 2003

I agree that A1-A6 were a way to record the current human world, but I believe that they are actual robots who carried these information with them . I think the A2 records are either: 1. Way to introduce human information (like music) to them, OR, 2. A recording of music written by an A-2 series robot. If I am producing a robotic human clone, I think I would want them to have the human-like ability to produce art. Original music written and performed by robots would be a huge step forward, and it would be something I would like to keep for future generations.

I think sensei and other designed robots to record human experiences, period. What surprised Sensei was Alpha's ability to record BEYOND human sensory experience. This was not in their design documentation and was something developed (or evolved) by Alpha herself (or maybe something which Owner has given her). I think this tend to say that Alpha, in addition to human-like free will, has also the very biologically significate ability to evolve. This means that robots are capable of their own evolution, and continue to evolve even when humans are gone.

I think from what you said I can probably deduce too that Misage was probably not a A2, but a special A7 unit as well. She seemed too human and perfected to be an much older model.

I think Nai was talking about the difficulty of creating a male robot, that its hard for them to survive their "infant" stage and become adult robots (this notion gives rise to my belief that robots are ORGANIC, that the're mostly carbon-based and are grown into their adult form). I do think it make sense that female robots were probably not persecuted as badly as the male robots, but I don't sense any sort of hostility against the A7 robots at all. I still believe that the hostility existed before the A7 series and that the A7 are sheilded from their own past by the human creators. But, since it pretty certain to say that we saw no record or even memory of the A1-A6 models, that the history must be pretty bloody and violent. Even sensei, the robotic genius, know nothing about them... or could she be lying to Alpha and Kokone? Could she in fact be part of the cover up? That she wished no A7 model to ever know what happened to their ancestors? Ai... I think that's more likely. It's possible that Sensei never worked on pre-A7 series, but know nothing about them? That's kind hard to believe coming from a well-educated robotic expert. It's like Stephen Hawkins knows nothing about Einstein. Sure he didn't come up with Relativity, but to say he knows nothing of the past? Hmm... suspect.

- Jeffrey Chen
Wednesday, August 6, 2003

> Robots and music

Well, given that there is already computer generated music these days it is not necessary to have a robot attached. (Experiments in music now uses EEG's to figure out what is good for people, don't be surprised if in a few years hit music contains subliminal signals based on this to make it more popular).

Hence, I am of the opinion that the people collected the required information for the A1-A6 series, culminating in the final robot form for the A7 series. It is pretty hard to tell either way, as there is little information provided.

> Beyond human sensory experiences

Both Alpha and Director Alpha appear to have the same capability, however it appears as though Sensei was present for the first prototype, but was later gone for the 2nd and 3rd ones (she met the Director Alpha at least once, though), hence she was probably not aware of this capability (which seems to be solely to pilot crafts and similar devices).

> Ability to evolve

Naturally, I wouldn't personally design a robot -not- to evolve! Biologically? Now we're treading into Amitage III territory... it depends whether you feel like being God (and give them free will, with no Asimov laws attached) or the other way around.

> Cover ups?

It is possible, but I suspect it is more likely that the Sensei fell out of contact with the engineers of the A7 series, explaining her lack of knowledge on them. What happened when the A7M3 series was released is still ambiguous, though... there simply isn't enough information to draw any serious conclusions, unfortunately!

It is possible that your opinion is correct, as it does appear as though Alpha knows exactly what was going on in the early days, whereas Kokone is striving to find out. (If this is the case, neither Alpha or Sensei are particularly eager to talk about it, and Alpha isn't really interested - possibly a reference to a 'bad' past she doesn't want to remember).

- PC
Wednesday, August 6, 2003

Aiya, this forum does make it hard to do quotes or links…

>Hence, I am of the opinion that the people collected the required information for the A1-A6 series, culminating in the final robot form for the A7 series. It is pretty hard to tell either way, as there is little information provided.

Hmm, yeah I guess this notion is kinda odd to me... I thought that if peopele would be gathering information about how to make a robot, they won't call that stage an actual prototype. My idea was that actual robots existed for each A number, maybe the A1 is something silly like the Honda Asimov, but a real robot nontheless. I thought that each number means a more advanced model of robots, and finally the A7s which is almost identical to human beings. Of course you may be right too...

>Both Alpha and Director Alpha appear to have the same capability...

You're right, I've forgotten that Director Alpha can also merge with the Tappon and even Alpha herself. I've also thought the first A7 was the Director though. My guess is Owner build both Alphas and implanted within them the same circuitry. I just came up with the fancy idea tht Alpha "grew up" like a normal kid with Owner, maybe Director Alpha also "grew up" on the Tappon, under the protection of the Scientists on board. I just have another thought, remember what Sensei said about the behavior of the first prototype she meet? Maybe that's how they were when first "created"; similar to Misago, they were unruly, a bit anti-social, and love being nekkid. Maybe From this stage, the Owner slowly nurtured the Prototype A7 models (the 2 or more Alphas) into the lovely ladies we know today. Wow, what does that make the Misago then? HOw come she didn't mature like the 2 Alphas? Let's say there are 3 A7 prototypes: 1. Director Alpha, 2. Misago, and 3. Alpha the Cafe Owner. 1 and 3 became "mature" and human-like beings (I would say D-Alpha act pretty similarly to Alpha), but somehow #2 became the Misago? How did she end up a fish-eater with fangs?? Wow, so many mysteries, so little clue :) But these 3 robots must be intimately related.

>Naturally, I wouldn't personally design a robot -not- to evolve! Biologically? Now we're treading into Amitage III territory... it depends whether you feel like being God (and give them free will, with no Asimov laws attached) or the other way around.

Well, I guess it would be a goal but must be extremely difficult to design a self-evolving robot. Yeah I think they are biological cus 1. Nai mentioned that they do grow, and 2. Kokone said that before her job, she was "trained". Never a mechanical word like "assembled" or even "created". Plus we know their skin is self-healing, and they do get sick (from food)... I would even venture a guess that they are 100% biological; not naturally produced organic parts, but aritifical. I mean we are at the stage where we can grow a ear on a rat's behind... who says we can't manipulate cells like we do with metal in the future? The question in my mine is their brain... is that also organic or a bunch of nerve attached to a supercomputer? hmm....

I believe the goal is to create something which can survive in the post-extinction Earth. Where they will have: 1. very little protein food source, and 2. Very small population size. In order to survive this world, even with technology, they have to be self-repareable or self-healing. I can't imagine they would require metal parts that would need an whole industry to support.

- JC
Thursday, August 7, 2003

> A prototypes

Well, as a programmer this notion is not odd. The more important thing with the A prototypes is the AI, not really the body. It would be infinitely easier to deal with a AI that ramps up to a body than to build an AI inside a body already (unless you knew what you were doing).

To be honest, the first AI's that will pass the Turing test will most likely be IRC or IM bots. You can see this happening today already what with Japan's "Virtual GF" (or "Virtual BF") SMS project which appears to be rather successful.

> Misago theory

Some things don't match up so I'm reluctant to make any firm conclusions. As to what happened - who knows! (If Owner turns up (ever) some of the mysteries would be over, though).

> Biological robots

Yes, there are quite a few hints about this throughout the series that they are biological or at least, semi-biological to a degree. Quite an interesting theory you have there, which goes along the ideas that humans were trying to making something in their image that was capable of surviving in the present Earth conditions.

This matches Hyperion's 'cybrid' theory, where the disembodied AI's built 100% human bodies, but were controlled by the AI's and linked to the Internet (the metasphere).

> Other thoughts

Well, since at the moment there's not a lot of info about the whole setup of the YKK world, we'll have to fit it into the "unresolved mysteries" basket (like the mushroom like buildings, the Water God, the Misago etc).

I get the feeling that Ashinano intentionally glosses over these details as it's more important to concentrate on what makes YKK great rather than to dig into the small details and wonder about the who, what or why of it all.

As Alpha would do, we would rather appreciate the beauty of a sunset than worry about the air pollution turning it that beautiful red and purple colour!

- PC
Thursday, August 7, 2003


I ended up writing a detailed response to this over on the other forum since it was easier to quote that way....




- dDave
Friday, August 8, 2003

The plants can't all be random mutations. They are more likely engineered.

The giant sunflower that yields one crop then dies would be one of these. The plants with light stalks would be another. Are there any plants that are bioluminesent in nature?

Don't know why someone would want giant persimmons or chestnuts though. Giant chestnuts for chestnut flour maybe.

- Mike Webster
Thursday, August 28, 2003

Well, in PositioN they do have schools, and both Musashino and Yokohama seem like large towns, even if they shrunk in population, with plenty of young people. I think the reason Takahiro and Makki got home schooling is because they live way out in the boonies. As for the series robots, even today plenty of scientists try to make robots capable of walking on two legs, although there is little real-world application for such machines. They probably created the robots just because they could.

- Daniel
Saturday, October 25, 2003

I don't think PositionN and YKK are in the same universe though. Makki and Taka got home schooling cus they are the only kid around in their town. If they lived in Yokohama I'm sure there still some school left, as some babies are still born. The kicker still is that not enough babies are born to replace those who died. Human beings are dying out very, very slowly. Notice how empty the school library Kokone visted was? Not a single kid there reading or playing.

I'm sure you would create robots just because you can, but why would you so keen on creating a robot that's even more human than us? Won't that be really scary to someone in our world? Yet in the YKK world robots are accepted as normal part of society. This denotes that they serve a purpose to humans that was not openly announced; I simply speculated that human beings create them to be so human to carry on the human legacy, and almost all human alive in that day and age has come to accept them as the future of mankind.

More I thought about this the more I'm impressed with Ashinano. How else can you have a world where such a realistic humanoid robot can co-exist peacefully with human beings? The man is a genius.

- JC
Wednesday, November 5, 2003

Won't robots similar to humans be scary? I guess, but that's what they said of the automobile and the telephone when those two inventions first came up. "Tools of the devil" indeed. I really do believe that what we see in the village where Taka and Makki grew up to be representative of the whole of Japan and the world. In PositioN, Keiko mentions that there weren't amny kids aroud her age when she was small, but we see plenty of classmates in other chapters. I think Japan (maybe the rest of the world) is in a retractive population growth stage. Notice how no one but the Alphas mention siblings. Likely, culture has evolved in a way where it is subconciously considered odd when a couple has more than one kid, which means there will always be less people in a jeneration than in the one before it. This sort of behaviour is already happening in several countries in Europe, where the average number of kids in a family dips below 1.6. As for PositioN and YKK being different worlds, I don't think they feel any different, but I don't have any arguments for or against it yet.

- Daniel
Monday, November 10, 2003

Have we seen any evidence of a political (or military) administration of the world? There are borders and crossings, sure...but no police, no apparent leaders and hardly any social obligations. How could there be no authority? Is this a world resigned to drifting away?

I would expect a daimyo or a crowd of yakuza to lurk about until the end. But it's not that way. Everyone seems...hushed. Like their collective breath has been knocked out.

I mean, this is Japan. Have we even seen a festival, something especially local that should have survived even in a small community? Are shrines attended (and tended)? All the ties that bind a community seem to have fallen away, without the anarchy one might expect. Is this the post-anarchy world?

I think, too, that whatever defined this state of affairs was fairly recent. The street lights in the submerged towns are still functioning. The ice caps would have to melt to raise the sea level. But unlikely it could happen so fast that the cities wouldn't be stripped and evacuated. That is a puzzle. The cities are just there, underwater...but where are the people?

There is a creepiness about this, behind the sunny daydream. Both Kokone and Alpha carry guns...both have been ready to use them. If the A-7s are shielded from the history of robot development, why the guns and the anticipation?

- seaweb
Tuesday, November 18, 2003


There is some sort of administration, but nothing on a country wide level any more. Alpha tried to visit a seat of government on her travels in chapter 66.


The cities and prefectures are now referred to as "countries", and the words they use reflects back to the first Japanese histories long before the country was unified.

And as far as shrines and festivals, don't forget that Alpha lives way out in the country. We don't get to see much "normal" life except when the story centers around Alpha's trips to Yokohama, or Kokone in Musashiho. So while it's true that the population is in decline, it's in *gradual* decline. It just seems more extreme do to Alpha's isolation.



- dDave
Tuesday, November 18, 2003

But there *are* festivals, remember the firework rocket? To me it looked like the old Nike-Ajax defence systems.

Also the new year celebration is a bit like a festival; many gathered.

- C_P
Friday, November 28, 2003

One thing I noticed about Director Alpha, was that why physicaly she seems like Alpha, in close-ups her face seems much more similar to Misago's than Alpha's. Could that have anything to do with when and how they were built you think?

- Thistledown
Monday, December 8, 2003


Director Alpha (A7M1) was completed considerably before the A7M2 prototypes (such as Alpha). That could easily account for the difference.

Although many folks think that Misago is a robot, I personally don't believe so.



- dDave
Monday, December 8, 2003

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