After breakfast, a walk around the island was part of his daily routine. In the pleasant rays of autumn sun and breeze, Dr. Paradigm, a Gear — a type of autonomous biological weapon — was in high spirits. The seagulls flying overhead, the sound of the waves… The whole world felt at peace.

After the Crusades, Gears were released from the controlling curse of Justice and continuously relocated from place to place, avoiding contact with humans, before finally discovering somewhere they could settle in permanently after several years. Here, they secured their long-sought tranquility. As Paradigm walked along, humming a tune of his own composition to the lyrics “God's in his Heaven, all's right with the world,” he saw one of his compatriots running towards him from up ahead, sobbing.

“D-Doctor?!”

“What in the world could have happened that’s got you in such a panic, dear Geroppa?”

“My head… I-it hurts…”

Upon closer inspection, a large bite mark could be seen on Geroppa’s head.

“Oh dear. Bitten again, I see…”

It seemed something was chasing after Geroppa. Great tremors shook through the earth as a massive creature approached. It was a familiar sight.

“Now, now, dear Bonebiter. You mustn’t gnaw on Geroppa. I always have to remind you of this.”

“Bwoooooone…”

In response to being scolded, the dragon-type Gear bioweapon roared lonesomely, and Paradigm sighed. He understood that it was an instinctive behavior, but he was utterly exasperated that, no matter how many times he warned it, Bonebiter would not stop preying on its own kind.

“Day after day, it’s always the same with you fellows. Should I be delighted in the day’s tranquility, or despair at this critical situation? It’s difficult to decide.”

The doctor crossed his arms and muttered. Suddenly, something silently flew by and spoke in a high-pitched voice into Paradigm’s ear.

“Doctor, doctor! It’s, it’s horrible!”

“Oh, don’t startle me, Assistant Bonnie. How many times must I tell you not to yell right next to my ear…”

“F-forget that and come on, please, urgently!”

Assistants returning to the laboratory darted through the air frantically. These women were homunculi created by Paradigm through the application of Gear cell technology.

“Tell me what’s wrong, my children. They say time is money, but rushing never brings good results.”

“You can lecture us later… Just look at this, please!”

“…Agk — is this..?!”

Paradigm’s gaze fixed on the monitor of an instrument that observed the Backyard. The cursor indicating fluctuations of numerical values displayed movement completely unlike its usual pattern.

“This is…?! Is space being minutely distorted? What happened?”

He reached for the console and input a code.

“The source of the distortion… is this?! Bonnie, assistance. From your terminal, increment the millionth digit of the Dirac constant by one, consecutively, please.”

“Y-yes! Well, um… The H-bar has… This is it! W-wow. The distortion graph just got even bigger!!”

“As expected! Assistant, continue.”

“Yes! Ah, this time the orientation changed! It swung all the way to the other side!”

“Good. Keep it secured in that state. No, that won’t do. The calculations won’t hold. Assistant. This time, subtract. Slowly bring it back.”

“Yes… Carefully. Huh? The cursor came back!”

“Alright, that’s it! Lock those values, please. Assistant Bennie, lend me a hand. We need the same values over here next.”

The other assistant, Bennie, who had been idly watching everything from on top of a book, slowly rose to her feet. Paradigm pointed at another instrument console.

“I see. As expected of you, doctor! You’re calculating the shape of the object by observing it from different positions using different devices!”

“It’s classic trigonometry, nothing special. The magic-wave occurrence rangefinger is my invention, however. Wait, nevermind that now. This is… A sphere about 1.7 centimeters in diameter? The bipolar theorem at this boundary… An interspacial gate between this world and the Backyard!!”

“Ah! The cursor’s oscillation range… Ahh, it vanished…”

“Bennie, assistance. What’s the recording say now?”

“Log, all checks good.”

“Alright. Output all the instrument logs after you secure the constants…”

“…Understood.”

A few minutes later, Paradigm was in a tank… or, rather, in his private room. This was a room designed specifically for his body, which could only breathe underwater. His assistants were seated at their desks, waiting and watching him read the data. His face was stiff with tension.

“Is something the matter, doctor?”

“Ah, well… Let me explain to you what I’m seeing in the output data…”

“…Y-yes.”

“The sphere we witnessed earlier acts as a kind of boundary between this world and the Backyard. The Divine Step wavelength optimized for the observation of the Backyard, and directed towards the sphere’s center, returned an undefined value. Conversely, the Divine Steps wavelength in our world returned real numbers. In other words, the inside of the sphere is our world. Additionally, the molecules that compose this gate appear to have undergone special magical manufacturing. Based on the absorption rate of the magic lightwaves, I am certain this is the case.”

"Well, uh, what does that mean?”

“It mean that it's very similar to the unique code I use to observe the Backyard.”

“Forgive me, doctor, I don't know how you observe the Backyard.”

“Ah, I see. I never taught that to you, did I? …Simply put, I observe the Backyard from our world by ‘spoofing’ the Backyard’s theorems with the theorems of our world. This is the absolute best that I can do, sending real numbers to the Backyard — physical interference is completely impossible… However, that sphere was composed through physical interference with the Backyard from our world. In other words, someone other than me has succeeded in making physical contact with the Backyard first.”

"Huh… Does that mean there's someone smarter than the doctor, by any chance?"

"I'm terribly sorry to say so, but that’s how it seems. Well, let's set that aside for now and address the real question..."

"Question..?"

“Who it could be. I have an idea, although it's somewhat disconcerting.”

"Eh, who is it?!"

“As I explained earlier, I use a 'spoof' code to observe the Backyard from this world. However, this code is actually not my original creation. It is a modified decoding of a portion of the source code extracted from the genetic information contained in Gear cells."

“Gear cells?”

"Yes. …The molecular bonds composing that earlier sphere are riddled with code quirks common to Gear cells… In other words, I am… displeased to report that the sphere was probably created by… ‘That Man.'"

"That Man... is the Gear Maker?!”

“The Gear Maker is him, you know. That fiend who started the Crusades…”

Sleepily raising her head to join the conversation was Bunnie, the older sister of Bonnie. Compared to her hard-working and modest younger sister, she had a somewhat headstrong and lazy disposition.

“Mm. The creator of our parents, the Gears. A horrific villain who is said to have changed his form again and again, and has lived for several hundreds of years. But to interfere directly with the Backyard… That’s too far beyond the realm of humans..!!”

The Backyard defines all laws of the material world, and is a higher-dimensional space that produces events or phenomena. Since its existence was hypothesized at the end of the 21st century, research on it progressed among a certain few scientists. However, humanity has yet to prove its existence.

“…What do you intend to do?”

“I’m unsure. But if that one has reached the Backyard, then this is something far worse than the Crusades!”

“Heey, I’m dying to understand what’s going on, can someone explain it to mee?”

“The Backyard is a higher-dimensional space formed by a collection of densely compressed information that defines and controls this world.”

“…Doctor. I’m sorry, but I don’t understand that at all. Explain it to me in human terms.”

"Mm-hmm?"

“You know, sis. Here’s an example story. The Backyard is a place where 1+1 becomes 2. What do you think happens when someone bad comes to that place and causes some mischief that makes 1+1 become 3?”

“…1+1 is 2, I thought? It can’t be 3, right?”

“Yeah, that’s true, but there’s a trick that makes it become 3. Cut an apple once, and it becomes 3 pieces.”

“That's very convenient!”

“Come on! It’s not about convenience, all the laws of physics are being overturned! The world will collapse!"

“Sorry, I don't understand your explanation either..."

“In any case. I thought we wouldn’t ever be affected by That Man’s influence until now, but I can’t say so anymore.”

“Doctor, why don’t you try contacting Mr. Izuna?”

"Oh, yes! I should let him know about this unusual situation..."