How to Build a Yandere Harem 【R】 - Chapter 16
Chapter 16 – Master of the Dungeon 【3】
Things I want to ask? I’ve got a mountain of them.
But what I want to ask most right now is where Mel is.
“If you mean E-R2WCR5486425315168, she is currently with Ori. She is in the middle of hearing about this world from Ori at this very moment, so please rest assured.”
No, hold on—I’m the one with you right now, aren’t I?
Or are you telling me there are multiple of these creepy things?
Give me a break.
“A little off. Ori is a one-of-a-kind existence across all dimensions. In other words, the Ori before your eyes and the Ori with E-R2WCR5486425315168 are the same Ori.”
That makes absolutely no sense.
In the macroscopic world, one thing can’t exist in multiple places at the same time.
Even if I take a hundred—no, a million—steps back and consider the microscopic world of quantum mechanics, what Ori is saying is still impossible.
Right now, I’m observing Ori.
Which means Ori’s position is already fixed, and she’s in the state of existing here.
If that’s the case, another observer in a different place—Mel—shouldn’t be able to observe Ori.
And conversely, if Mel is already observing Ori, then Ori shouldn’t be in front of me.
Schrödinger’s cat makes this easy to understand.
If I’m looking at a dead cat, Mel can’t be observing a living cat.
But what’s happening right now is exactly that impossible situation.
By the way, Schrödinger wasn’t “the guy who put a cat in a box and abused the poor thing with poison gas.”
He was a theoretical physicist who proposed the Schrödinger equation, a fundamental equation in quantum mechanics, and helped build the field’s development.
That cat-in-a-box thing is just a thought experiment.
Do not get it twisted.
Anyway, back to the point.
So whether in the macroscopic world or the microscopic world, it should be impossible for Ori to exist in front of both me and Mel at the same time.
But according to Ori, “the Ori in front of you and the Ori with Mel are the same Ori.”
I really don’t get it.
The only two things I did understand were that Ori is a living being, not an object (since she said she was “with” someone), and that Mel is safe. That part is a relief.
But then why am I here, separated from Mel?
The simplest answer is that Ori teleported me.
But if Ori just wanted to tell us the truth of the dungeon, it would be more rational to teleport me and Mel together and explain it once, rather than sending us to different places and showing up in front of each of us separately.
And yet, Mel and I are receiving separate explanations in different places.
Which means Ori had a reason to keep us apart.
What for?
And why is Ori calling us by a combination of letters and Arabic numerals?
And in the first place, who is this “Ori” who calls herself Ori—this “she”… even though I don’t actually know if she’s female or not?
“Ori is Ori.”
No, sure—reading my mind and answering instantly is convenient, since I don’t have to say the questions out loud, but that didn’t answer anything.
And I just asked three questions in my head, but Ori only answered the last one.
Then what happens if I keep thinking up questions for a full minute at, say, ten per second? How would she react? Would she panic?
Now I kind of want to try it.
“Hee-hee-hee. What an interesting question! What a delightful question! In that case, I would convey the answers directly into your brain, but if the amount of information becomes too immense, there is also the possibility your mind could break, you know? Come now—shall we try it?”
No thanks.
◆ ◆ ◆
After that, I asked Ori all sorts of questions.
Ori answered every single one, but the answers were so difficult that it took a long time to understand them.
If I summarize Ori’s answers in a simpler way, it comes out like this.
-
- About Ori
This “dimension” contains countless worlds, including the world I was in, the world Yamada was in, and the world Mel was in.
Here, “dimension” refers to the total space in which worlds can exist, and its capacity is infinite.
However, it’s not like countless worlds existed from the beginning.
In the beginning, there was only a single world created by someone, along with Ori.
Her reason for existing was to create new worlds in this dimension at a fixed cycle.
Ori didn’t know who created her, but she did know her purpose.
So in accordance with her mission, she created worlds one by one.
And that’s how this dimension came to contain countless worlds.
It’s easiest to think of the dimension as a hard drive with infinite capacity, and each world as independent software—an app, a game, that sort of thing.
If you think of it that way, then whoever created Ori was a programmer, and Ori’s true nature is a program that creates new software at fixed intervals.
Well, that’s only an analogy. In reality, it’s more complex and harder to understand.
-
- The birth of the dungeon
This dungeon, like the countless other worlds in the dimension, is one independent world, recently created by Ori.
And just so it’s clear, “recently” here is on a completely different scale from what we’d call “recent.”
Before creating a world, Ori randomly selects fifty existing worlds and demands “ideas” in the form of “works” from each world’s chief god.
The form of the work can be anything—games, novels, manga, videos, models, songs—literally anything goes.
The chosen world’s master is obligated to provide one work to Ori.
If they fail to fulfill that obligation, the world’s master is erased.
Many gods choose erasure, but the ones who don’t send Ori a work.
In that case, gods who can create works do it themselves, but gods who can’t—or can, but can’t be bothered—make their own creations do it instead.
There are all kinds of ways to make them do it.
Ordering them through an oracle, appearing in their dreams to ask, dangling prizes or rewards or special perks so they create voluntarily, and so on.
Among the worlds randomly selected this cycle for idea solicitation was my world.
My world’s master decided to have his creations make games, pick the best one, and send it to Ori—so he held a game contest with an absurdly massive prize pool.
At the time, the theme Ori planned for the new world was “despair” and “dungeon,” so the genre became a ryona game, and the judging criteria became the quality of the death scenes and how vicious the content and scenario were.
That’s the background behind the ryona game contest—aka RyonaCon.
In other words, the true sponsor of RyonaCon wasn’t a human. It was a god.
Come to think of it, there were plenty of suspicious things about that contest: it popped up out of nowhere one day, the genre was way too niche, the prize money was way too high.
Normally, entering something that shady should’ve been unthinkable, but because the sponsor seemed like a trustworthy person, about thirty teams applied.
I’ve said it before, but I applied to RyonaCon too.
Back then, I was a first-year high school student, living alone and going to school on my parents’ life insurance payout.
Up through high school, I could manage, but if I wanted to go to college, I’d need money.
While I was agonizing over whether to get a part-time job, I happened to see an ad for RyonaCon.
And lured by that gigantic winner’s prize, I applied on a whim, figuring it couldn’t hurt.
I tried to make a ryona game by using my experience building RPGs as a hobby.
Anyway, back to the point.
My world’s master sent Ori the game he considered the cruelest among the entries—namely, the work that took first place in RyonaCon.
But Ori didn’t choose that work.
The one she chose was an extremely realistic game created in another world: Hope Is Everywhere in the Dungeon!
And so, this world—“Rana,” built on that work—was created.
Once a new world is created, the next step is selecting the being that will manage it: the “master of the world.”
Ori’s role is strictly “creating new worlds,” not “managing created worlds.”
The method for selecting a master of the world is as follows.
First, from each world, one being is selected whose aptitude factors needed for world management are the highest.
Then, the selected beings are teleported as “offerings.”
When someone among the teleported offerings fulfills “specific conditions” and shows the will to become the master of the world, that being becomes the master of the new world.
Those “specific conditions” differ by world.
In the case of this world, they are “reach the lowest level of the dungeon and defeat the Demon God.”
By the way, the aptitude factors presented for managing Rana this time were the following eleven.
Factor 0: Getting run over by a truck
Factor 1: Clearing the dungeon (meaning the game, not the real world)
Factor 2: A student or working adult who thinks they’re ordinary, but actually isn’t
Factor 3: Going to a convenience store
Factor 4: Being in a near-death situation
Factor 5: Parents deceased or absent
Factor 6: Having the game’s strategy completely memorized
Factor 7: Getting stabbed with a blade while protecting a girl
Factor 8: Experience refusing to go to school
Factor 9: A programmer or software creator
Factor 10: The presence of a handsome or otherwise superior classmate nearby
These aptitude factors are for managing a world, so to be selected as an “offering,” you need to meet at least three of them.
If, among the will-bearing beings in a world, none have three or more factors, then that world cannot provide an “offering,” meaning even if it submitted a “work,” the world’s master would still be erased.
In this case, if your world has trucks and convenience stores, no problem—but if it doesn’t, you can’t meet the factors.
So world-masters whose worlds lacked concepts like trucks, convenience stores, programmers, or schools tried to force their creations to have the aptitude factors by changing definitions, warping perceptions, or suddenly supplying convenience stores out of nowhere.
Apparently, one god even redefined “gas” as “truck,” the act of “breathing” as “being run over,” all “living things” as “programmers,” and “homes” as “convenience stores.”
What the hell did that god do?
Wouldn’t that mean you’d get isekai’d just by trying to go home…?
Also, to satisfy Factor 1 and Factor 6, each world’s master informed their creations about the existence of Rana.
Methods included oracles, myths, murals, legends, oral traditions, ancient books, games, announcements, manga, interviews, anime, dramas, and compulsory education.
Setting everything else aside, I’d hate to live in a world where you learn ryona games in compulsory education.
…Okay, I got sidetracked.
My world’s master swapped the former first-place RyonaCon work down to second place and made the work Ori chose first place.
Then after distributing it online for free, he announced it via a “creator interview.”
That was the outcome of RyonaCon.
However, that game was overtechnology beyond what Earth could make, and on top of that, most of the submitted ryona games were side-scrollers, so the god changed it into a side-scroller before distributing it.
That’s why the game is 2D, but the actual dungeon is three-dimensional.
After telling me all that, Ori said:
“Yes. The original first place was the game you made, Mindbreak—Bodies and Minds Trained into Dolls. Ah, that work was magnificent! Absolutely superb! While playing, Ori couldn’t stop trembling with excitement. I could not choose it because it had too few death scenes, but if there had been more death scenes, Ori would have selected your work. Ahh… what a terrible shame.”
Ori praised the game I made with a face that screamed unbearably disappointed, but well—this is that.
It’s the same as what’s written in a rejection notice from a company: “After careful consideration, we regret to inform you…”
In other words, a formal consolation.
I half-listened and asked my next question.
-
- About the creator
Once the new world’s master is decided, Ori waits—by her time scale—for about one million years until she creates the next world.
Ori counts that period as a “cycle.”
In the cycle right before she created Rana, Ori gathered ideas in the form of books from four worlds and created a new world.
The other world-masters chose erasure, apparently.
So in exchange for one world being created, forty-six worlds were erased… is that really okay?
“Of course it isn’t okay. It is a situation that should deeply concern you. We must do something to increase them again.”
Saying that, Ori stared right at me.
Sounds like she has her own problems, but I have no reason—or obligation—to worry about someone else’s work progress.
I ignored it and focused on gathering information.
Alright, continuing.
Eventually, one being with the highest aptitude factors was selected from each world and teleported into that book-world as an offering.
They cleared that world according to the novel’s content, and the last surviving one became the master of the world.
Apparently, he was someone from the world I came from.
Given the countless worlds out there, the odds of the same world being selected consecutively are basically zero, so even Ori was a little surprised by that coincidence.
After becoming the master of the world, he split his world into five and numbered them World One through World Five.
Then, after setting specific magic in each world, he established the following rules:
“Each world contains magic that represents that world’s traits.”
“One being cannot activate the same world’s magic simultaneously. The only magic that can be activated at the same time is world-magic from different systems.”
That matches the laws of magic Mel taught me.
The reason is that her world was created by him.
After becoming a god, he created humanity, other races, demon lords, monsters, and heroes, then spent his time watching their sagas.
But after five hundred years, he got bored.
After that, he abandoned his world and killed time doing nothing.
Then, after a long time passed and the next cycle arrived, his world was selected by Ori.
Bored to death, he went all-out and made an extremely realistic game.
First he built an actual dungeon, placed the monsters he’d created as the dungeon’s monsters, and personally designed the boss.
Then he gave the boss and monsters the magic skills he’d set, input their patterns, and set mana recovery to infinity.
Also, if the teleported beings could use magic, the difficulty would drop drastically, so he set restrictions on mana and abilities to neutralize them.
However, he didn’t restrict interactions between the teleportees.
He judged that cooperation in that environment was impossible anyway, and that letting them interfere with each other would make it harder to clear.
Thanks to that, Mel and I were able to clear the boss stage together.
If there had been restrictions, the boss room would’ve become an instanced dungeon, and Mel and I would each have had to fight the boss alone.
After the game was finished.
He created Hanako, used her to do debugging, and then sent the game he made to Ori.
That’s how the game Hope Is Everywhere in the Dungeon! was chosen as the background for a new world.
That bug on the second floor happened because he debugged alone.
…So the creator of that game was a god?
I figured he wasn’t a normal human, but I never expected he wasn’t human at all…
Because his game was selected, he obtained the right to set the aptitude factors for selecting offerings.
After thinking about what to specify as aptitude factors, he chose the standard template from isekai-transfer stories he loved reading in his original world.
Then, to teleport someone from his world, he informed his creations about Rana and taught them how to get there.
As a result, Mel ended up being teleported here.
-
- About the dungeon
When an offering is teleported into the dungeon, the offering’s physical body is preserved at the location of Rana’s main system—“Rana” (the world and the main system share the same name)—and only the mind is sent into a “new body.”
This “new body” looks the same as the original body, but follows the dungeon’s laws rather than the original world’s laws.
Selection and teleportation happen simultaneously across all worlds, but if someone dies right before or during teleportation, a resurrection process becomes necessary.
The resurrection process proceeds in the order of “reconstruction of the body” → “transplanting the soul” → “fixing the memories” → “awakening consciousness,” and it takes a bit of time to complete.
That’s the main reason there’s a gap in teleportation timing.
The reason you don’t die even if you get killed mid-clear and your HP hits 0 is because this body isn’t your real body.
However, the mind is connected to that body, so you continue suffering forever.
Until someone clears the dungeon, there is no salvation for the offerings who have died.
-
- About the perk
If someone among the summoned beings defeats the Demon God and shows the will to become the master of the world, that being becomes Rana’s master and manages this world.
Ori calls the master of a world a “higher being.”
A higher being is immortal and can do anything.
Creating new beings, erasing existing life, changing the laws of the world, even creating other worlds inside their own world—everything is possible.
In other words: “Become the god of a new world, and any wish will be granted.”
Yes—surprisingly, what Yamada said long ago about the perk was correct.
Sorry for doubting you, Yamada-san.
I apologized to Yamada, who was still suffering inside one of those machines in real time.
There was no reply. Like a corpse.
Well, he isn’t dead, but still.
“Can you bring dead people back to life too?”
“Of course. If it is a creation you made yourself, resurrection is easy even after death. However, resurrecting a being that belongs to the world prior to teleportation is not easy. In that case, there are two methods. The first is to analyze the behavior patterns of the being you wish to resurrect from your own memories, create a new being—an event—and input behavior patterns and memory data into that event. Then that event will act the same as the being you wished to resurrect, so you could say you have ‘resurrected’ them.”
No, that’s not resurrecting them at all.
That’s just making a doll.
“U-Um. Is that so? You are thinking the same thing as most beings who become masters of worlds. From Ori’s standpoint, you are not yet higher beings, so you are merely events, but I cannot understand what the difference is. In that case, you must use the second method. That method is to bring in the target’s data, change their affiliation to the world you manage, and reconstruct them. In this case, the act of ‘bringing in the target’s data’ is the same as ‘summoning the target’s spirit body.’ But a target bound to the world’s laws cannot be summoned. For example, if the target you wish to summon is the foundation that composes that world—the ‘core of the world’—then it cannot be summoned. And to change the affiliation of a target with a high priority of existence, a price is required.”
The second method was a proper method.
I don’t like how Ori talks about spirit bodies as “data,” but maybe that’s what we are from where she’s standing.
That aside—summoning a spirit body, huh.
If that works, then my parents, too—
“Unfortunately, you cannot resurrect your parents using the second method. Your parents reincarnated into another world across the dimensional wall. They have now become beings bound to that world’s laws, so they cannot be summoned.”
Ori kindly answered even the question that had only just popped into my head.
I see…
So even if I become a god, I’ll never see my parents again.
“What are my parents doing now?”
“If I put it simply, your father has formed a harem. And your mother is one member of that harem.”
“W-What!? What the hell happened…? My dad was so serious, and he only ever looked at Mom… and he made a harem…?”
“Also, your father always says he is in despair, but in reality he is not in despair at all. The beings around him are the same. Because of that, your father is always spitting blood.”
“What kind of situation is that!? That makes no sense at all!?”
“It is exactly the situation I described, is it not?”
As usual, Ori’s explanations were hard to grasp.
But, well, there are a lot of things that bother me—still, for now, it sounds like my parents are safe. That’s a relief.
Yes. In that moment, I confirmed my parents were safe, and I was relieved.
My tension loosened, and without thinking, I blurted my next question out loud.
“I get that clearing the dungeon makes you the master of the world. Since I cleared it with Mel, do I become the master of the world together with Mel?”
Ori answered in a bright, cheerful voice.
“Ahh, Ori has been waiting for this question the whole time! I have been looking forward to it! I regret to inform you that the number of beings who may become master of the world is only one! Therefore, you and E-R2WCR5486425315168 must kill each other until only one remains! And with that, question time is over. Let us proceed to the next stage!”
What the hell.
Yamada’s information was wrong at the very end.
So yeah—he really was hopeless after all.





































