They say that when you commit a sin, the Sky God knows, Mother Earth knows, and you yourself know.

If asked which of those three knows first, devout followers of the Sky God might deny it, but the answer is you.

People about to do something wrong generally know it. They glance suspiciously around, fidgeting about without blending into their surroundings, until suddenly they tense every muscle and do the deed.

Then, if they get caught, they freeze as though someone has cut out a stretch of time, with only their eyes darting about. After that, they either bolt or play dumb and pretend to be doing something else.

That is proof that we recognize our own sins before anyone else does. A manifestation of guilt, you might call it.

Unfortunately, the Regressor had torn her conscience to shreds and scattered it across thirteen regressions. She didn't even have that.

"You agree too, right? I'll take care of it."

Correction. Her guilt was practically in the negatives.

What kind of circuitry did you need in your head to come out with "You agree too, right"? Why was she so certain I would naturally agree?

The Regressor's externally mounted, thirteenth-run thought circuitry truly exceeded all imagination. Maybe it was a blessing my mind reading only half worked on her. One wrong read could contaminate my own mind.

I immediately shouted to stop her from doing anything outrageous.

"Stop! You one-armed factory manager! What on earth are you trying to do?"

The moment I started to raise my voice even slightly, the Regressor swiftly swung Sky Cherry Blossom.

Heavenly Sword Art, Sheer Cliff.

The sword's stroke drew a boundary through empty air. The edge of a distant cliff, where the wind broke. The wind's path ended at the line Sky Cherry Blossom had drawn. For one minute, the wind would carry nothing through that space. Neither scents dissolved in the breeze nor sounds vibrating through the air.

That sword was seriously broken. Then again, it would have to be that good for the Regressor to carry it from the very beginning of a run.

As I grumbled inwardly, the Regressor muttered with equal dissatisfaction.

"Why? You're a convict laborer, aren't you? I don't know whether that's true or not, but either way, if you've ended up here, you're at odds with the Military State, right?"

"Well, yes. I'm locked up here, after all."

"Then there's your answer."

Sky Cherry Blossom spun in her hand. Catching the wildly whirling blade in one swift motion, the Regressor held it upright and glared at the other side of the door.

"I'll leave the people already here alone and cut down every Military State dog that comes down from now on. One at a time, as they arrive."

"Wait. Cut down what?"

"The Military State's dogs."

I could only open and close my mouth in disbelief.

So the Regressor intended to kill every member of the Military State who came here from now on. In all seriousness.

"I'll make this simple. Listen carefully. There are two kinds of people in the Military State. Those who want to control everything they can, and those who want to control even what they can't. And the ones over there are extremists even among the latter."

Having indeed kept her explanation simple, the Regressor reached an equally simple conclusion.

"So I'll kill them before they try anything pointless."

"Whoa."

"The lieutenant colonel is their lackey. So what? Killing her will get a response. Either they'll all come down here in a blind rage, or they'll just watch like cowards. If they come down, I'll kill them. If they don't, I'll leave them alone. Either way, there won't be any Military State left in Tantalus. Then I can protect the people here."

The logic was exceedingly simple.

Azi and Tyr, who could later become pieces of the apocalypse, were both fine. Meanwhile, I, the biggest wild card, wasn't actually affiliated with the Military State.

That left one variable: intervention by the Military State.

She would eliminate it. Entirely.

Was this... the Regressor's perspective?

Rather than untie the knot, she'd cut it with Sky Cherry Blossom. It was reasonable in a way, but wasn't she leaving herself a little too little room to maneuver?

I asked cautiously.

"Um, what about supplies? If you kill everyone who comes, won't they cut us off?"

"I have food in my Pocket. I stocked up in advance for emergencies. I'll share it."

"You were hoarding food all to yourself while the rest of us lived on canned beans?!"

Was this... the Regressor's preparedness?

"We could get hurt fighting the Military State! What if they keep dropping bombs in supply crates?!"

"The Military State isn't stupid enough to shower bombs on a place that won't cause trouble if they leave it alone. I can deal with basic bombs, and even if someone gets hurt, I can make simple healing potions... And if worse comes to worst, try asking Tyrkanzyaka. You could just become a vampire, couldn't you? Tyrkanzyaka would be delighted, too."

Was this... the Regressor's character?

"But we can't live here forever, can we? Or are you really planning to stay forever?"

"Not forever. There'll be a way out soon. If 'she' falls down from the surface, then probably... one way or another, it'll be over."

'Whether I die or she does, the survivors can escape. The bottomless pit will collapse.'

What I sensed from the Regressor was a vague anxiety and grim determination. She was like a gladiator putting her affairs in order before a fight whose outcome was uncertain.

This was the Regressor's resolve.

But...

But the thing was...

You couldn't die. That would end the world.

Whether the world rewound or some other apocalypse arrived, what about the people left behind?

First, stop her. I could think afterward. My expression clouded as I spoke.

"Um, the thing is, I just planted a little something. Could you wait until it takes effect?"

"Don't you understand? Those people are more dangerous than bombs! Even a mere lieutenant colonel might have something up her sleeve!"

A mere lieutenant colonel? They carried quite a bit of weight in the Military State, and she called them 'mere'?

Oh, right. You people could get away with that. Whew. Sometimes I really couldn't get used to the scale of things here.

When I continued to look uncomprehending, the Regressor clicked her tongue and lowered Sky Cherry Blossom.

"If you don't believe me, I'll show you right now. Here, watch. See what a lieutenant colonel does after coming to the bottomless pit."

Just then, I read an intention to leave from inside the Instructor's office. The lieutenant colonel had begun to move. The Regressor noticed her movements too and beckoned me closer.

Once I pressed close to her side, she gripped Sky Cherry Blossom and assumed a middle guard.

Heavenly Sword Art, Sheer Cliff.

She sliced through empty air. The sword of the heavens severed the tidings the wind would carry. Scents and sounds alike. Everything traveling through the air was cut off at the fault line. A wall of disconnected air surrounded the Regressor and me.

Then she pointed the sword downward. Wind billowed from Sky Cherry Blossom.

Wind, clouds, rain, and dew.

Compressed space unfolded, and dew and mist filled the suddenly expanded space. The mist that should have spread out into the world struck Sheer Cliff and bounced back.

Having summoned mist to blur our figures, the Regressor took hold of her sword again.

Heavenly Sword Art, Sky Mirror.

A mirage was the lingering image of light bent over a vast distance. That phenomenon was reproduced over a distance of barely one meter. Now the Regressor and I were concealed within the bending light.

A moment later, the Instructor's office door opened and the officer emerged. A stray breeze from Sky Cherry Blossom happened to brush past her hair.

Puzzled by the wind blowing in the bottomless pit, she looked around. Her gaze briefly passed over the Regressor and me, but she couldn't see us through our concealment technique.

The officer nodded to herself and headed for the stairs, her military boots clicking against the floor. With her hands clasped behind her back, she disappeared down the stairway.

The Regressor exhaled deeply.

"Whew. Doing that in a rush leaves me a little winded."

"A concealment technique? Impressive. She couldn't see us even right under her nose."

My sincere admiration made the Regressor feel a little pleased with herself, though she outwardly replied as if it were nothing.

"Hmph. It's nothing special. It blocks sound and smell and blurs our presence, but it doesn't work on powerful opponents who send streams of energy flowing out around them."

"Is this what you used when you tried to spy on me last time? It's an impressive ability, but every use you put it to is so sleazy."

"... Shut up and follow the lieutenant colonel."

The only sounds the technique could block were those traveling through the air. Wary of letting our footsteps be heard, the Regressor and I descended the stairs carefully.

The officer went all the way out to the courtyard in the bottomless pit. Taking up a position in the middle of the area illuminated by the daytime lights, she revealed a rubber ball in the hands clasped behind her back.

A jet-black rubber ball, durable, bouncy, and just the right size to fit in one hand. It was several times better to play with than my improvised leather ball.

The officer bounced the rubber ball against the ground a few times with hollow thumps. The resilient ball sprang back up like a spring.

With her preparations complete, she called Azi.

"King of Dogs!"

"Woof?"

Azi poked her head out from around a corner. The officer bounced the ball a few more times, then hurled it hard toward the far side of the courtyard.

"A present for you!"

The rubber ball sailed far through the air. After a long flight, it bounced a couple of times and rolled all the way to the opposite side of Tantalus.

Azi watched it, her tail swishing from side to side, then finally kicked off the ground as though she couldn't stand it any longer.

"Woof, woof!"

She chased the ball happily. Racing on all fours, she caught up and tried to scoop it into her mouth, only for it to bounce off her face. That excited her even more, and she went after it again.

After missing it several times, Azi finally took the rubber ball in her mouth and returned to the officer. With a crisp motion, the officer picked up the ball and offered some perfunctory praise.

"Well done."

"Woof, woof! Ball!"

"I'll throw it again. Here!"

"Woof!"

'Just as the report said. The King of Dogs isn't wary of me... Getting her to obey will be easier than I expected.'

The sight of the officer taming Azi while harboring such sinister intentions...

Watching it, I felt my heart crumble.

"No! Azi!"

"See? She's a lieutenant colonel, and the first thing she does is tame the King of Dogs. Isn't that suspicious?"

The Regressor muttered with her arms folded.

"I was right. They're the 'Lords of Creation.' People who tame Beast Kings to bend them to their will... There's no telling what they'll do next. Better to deal with them beforehand... Are you listening?"

"No, I'm not!"

Was that important right now? She was trying to snatch away the puppy I'd spent months working on!

Did she know how long I'd endured to train her? I'd struggled on even when my throwing arm had reached its limit. I'd cooked for her every day, petted her, and groomed her fur! And now she was falling for some uniformed officer with medals?

"Th-that fickle-tailed puppy! She brings you a slightly bigger, bouncier rubber ball, and you wag your tail at her straightaway?"

"Uh, because she's the King of Dogs? Oh, hey. Don't move. If you move too violently—"

"Not a chance! You think you can lure Azi away with one measly toy? I've spent months with her. I know exactly what she likes!"

Ignoring the Regressor, I ran straight back up into the prison. Taking the stairs two at a time, I reached my room, grabbed an armful of rubber balls and steel discs from the drawer, and rushed back out to dump them all on the ground in front of Azi.

Returning with the ball in her mouth, Azi spotted me and the discs and stopped in her tracks.

"Woof?"

"Azi, come here! You graduated from balls ages ago! We've finally broken the two-disc barrier. It's time to move on to three!"

"Woof, woof?"

Azi glanced between the officer and me, then dropped the rubber ball and ran straight over. I held up three discs in front of her and tossed them into the air at short intervals.

Azi sprang from the ground and caught one disc in her mouth. Then she kicked off the prison's outer wall, snatched the disc higher up, and finally stretched her body out toward the last one.

"Oh dear. Just a little short...!"

When she couldn't reach it, she simply caught it with her hand.

As Azi landed, I took the discs from her mouth and praised her.

"Using your hands is cheating, but well done. That's how it's done!"

"Woof! Woof, woof!"

I was petting Azi as she bounced excitedly at my side when the officer approached. Having lost Azi midway through their game, she glared at me with terrifying eyes beneath the low brim of her cap. Her military boots pounded against the ground.

"... Convict laborer. Why are you interfering with me again?"

I answered calmly.

"Territorial behavior, Lieutenant Colonel. If you want to get close to Azi, you'll have to get past me first."

"... You bastard. Do you truly wish to die?"

"Oh dear. Make a face that frightening and you'll scare away even a dog coming to greet you."

"A mere petty criminal dares address an officer of the Military State like this...!"

Just as the furious officer took a step forward, a voice spoke.

["Rein in your killing intent, soldier."]

The voice rose from the shadows. Rather than coming from vocal cords, it seemed to be created by the darkness itself vibrating.

The officer flinched at that ominous presence and clenched her teeth.

"Tch, Progenitor...!"

["What you do is no concern of mine... But let me make one thing clear again. Hugh is under my protection. Should you inflict any manner of harm upon him, I shall not stand idly by."]

The billowing shadows delivered a stern warning. It was like a demon speaking through the darkness, or perhaps the world itself issuing a solemn admonition.

As the officer shrank back before a voice that inspired something beyond intimidation—fear—I tapped the shadow and addressed it warmly.

"Tyr. If you're going to watch like that, just come over."

The voice that had seemed ready to swallow the world only moments earlier suddenly wavered. A little later, Tyr's somewhat deflated voice came from the shadow.

["I... No. As you said, how could people spend every day together? Some time apart is necessary, too."]

"Are you sulking because I said people couldn't be joined at the hip all the time?"

["I am not sulking. I merely thought you were right."]

"Then at least commit to it. You've planted eyes in my shadow anyway."

["... Then may I come over?"]

"Of course."

["I shall be right there."]

Immediately afterward, the underground armory door opened. Tyr flew over in no time, sitting demurely atop her floating coffin with her limbs tucked together. She had been waiting behind the door all along, ready to rush out at any moment.

The all-star lineup was assembled. The Regressor was still hiding with her arms crossed in disapproval, but she was on my side regardless.

Azi still liked me far more.

And Tyr went without saying.

The officer must have realized it too. This was the wall she had to overcome.

"You can't have Azi. If you think you can, try showing her a better time than I do!"

The officer glared daggers at me and bit her lip. But lashing out in front of this lineup would only hurt her. Before long, she gave up and spun around.

'He's openly keeping me in check. Does he know who I really am...? No, a mere petty criminal couldn't possibly know. Is this simply a struggle for control?'

Walking away from me, the officer made up her mind.

'It's a shame to use one so soon, but I have no choice. Of the three bundles that person gave me for emergencies, I'll have to use one...!'