The concrete ground drank the blood of the fallen, and the endless darkness swallowed people with stories of their own. In the bottomless pit, cursed even by benevolent Mother Earth, foolish children could not restrain themselves from committing yet another sin. The knight who had hoped to leave a single line in history had, in the end, departed this life along with the four young people who followed him.

Yet time, like a mighty river, carried everything away, tamping tumultuous lives down into the level ground of routine. Yesterday's deaths sank out of sight, unknown to anyone, stirring no hearts.

And my old daily routine returned.

"Woof!"

Mmm. Felt like it had been a while since I'd heard that alarm. I rolled over and reached out a hand. Azi rubbed her nose against my hand and arm, barking incessantly. When I still refused to get up, she even gave me a little nip.

"Woof! Woof!"

"Yeah, yeah, I know. I'm getting up."

I stretched luxuriously, rewarded my alarm with a pat, washed my face with today's water ration, and washed my hair with the water from the room next door. Refreshing. Add some warm morning sunshine and a cool breeze, and I couldn't ask for anything more.

I slotted an instructor uniform packet into my biometric terminal. The uniform spread over me, snug but not restrictive. Changed in an instant, I stuffed various odds and ends into my pockets and headed out. Azi stuck close beside me.

"Let's have breakfast and go for a walk."

"Woof!"

"For breakfast today, we have something fresh and clean from yesterday's new supply delivery."

"Woof, woof!"

"Canned bean stew. Sound good?"

"Woof, woof!"

What a relief. Maybe dogs just had bad memories, but she didn't mind eating the same thing she'd had yesterday. I should feed Azi nothing but beans from now on.

Now that I'd had a hearty breakfast, it was time for the next job.

I went out into the yard. Azi followed, eyes sparkling at the prospect of playing fetch.

Not today, you mutt. After all that playing yesterday, you ought to be satisfied. Were you insatiable, or had you already forgotten? Couldn't your memory improve just for this?

I pushed her aside as she kept darting ahead of me and looking back expectantly.

"Don't get in my way. I've got an incredibly difficult job ahead of me today."

"Woof?"

"I have to wake up an elderly lady who sleeps in and has terrible sleeping habits."

With grim resolve, I headed to the underground armory where the vampire lived. Even in the darkness, the sinister aura billowing out seemed almost visible. I swallowed, approached the armory's iron doors, and shouted as I pounded on them.

"Trainee Tyrkanzyaka! Wake up! The sun's high in the sky!"

"Woof?"

Azi looked up at the sky in puzzlement. There wasn't so much as a speck of sunlight to be seen inside the bottomless pit. She tilted her head.

So what? It was definitely high in the sky outside. If you wanted to argue, bring the sun down here.

I kept pounding on the armory doors with my hands and feet.

"Wake up! How long are you planning to sleep? The Resistance invades from above, and you snore away. This place nearly collapses, and you snore away. What, does dying once excuse everything? Does death put an end to work? To taxes? If you can move your body, you should at least think about contributing to society—!"

"What is all this commotion so early in the morning?"

As I hammered away, the underground armory's doors opened at a leisurely pace.

"What an ill-mannered fellow. If you come as a guest, ought you not wait for your host to make herself presentable?"

"You're in a coffin anyway. What do you need to make yourself presentable for...?"

I was about to add something, but shut my mouth at the sight of the vampire through the gap in the doors. I'd naturally expected a voice echoing from inside a coffin, but she looked different from usual.

"Oh. You were already up."

The floating cedar coffin was as tediously unchanged as ever. But the vampire was sitting on top of it. With her legs demurely together, her hair swept up with an antique hairpin, and a parasol resting lightly against her shoulder, she exuded the elegance of a princess from an ancient dynasty. The jet-black parasol, fashioned from gathered darkness, swayed like a willow leaf on her slender fingers, as though it weighed nothing.

Her old-fashioned garments hung in flowing layers. The sleeves were so wide that glimpses of snow-white skin showed through their openings. The lavish use of fabric was an indirect display of leisure and wealth. The Military State would have had a fit, but people really had dressed that way in the past.

As the vampire took a step forward, the enormous steel doors swung wide to either side as though welcoming her. The bright red brands etched into them shone. With excruciating slowness—or dignity, if taking your time counted as that—she emerged from the underground armory.

The iron doors closed behind her with a heavy thud. Perched atop her coffin, the vampire muttered.

"It has been so noisy lately that I cannot sleep at all. How are three people louder than over a hundred used to be? With all that screaming, louder than a pig having its throat slit, one can scarcely live in peace. Honestly."

"Wow. Were you going to sleep some more if I hadn't woken you? You still haven't had enough? After a few hundred years, you'd think sleep itself would get sick of you and run away."

"... Enough. It was my mistake to argue with you."

She shot me a sidelong glare and steered her coffin forward.

"Why did you come out of your coffin?"

"If I have decided to wake, I must make myself presentable. Is that not elementary?"

Her reply was oddly sharp. She whipped her head around and fixed me with a piercing stare.

"Or do you have some objection to my dressing up?"

'Go on. Call me foolish again, as you did yesterday.'

What was with this sudden hostility?

Oh. Wait.

Was she sulking because I'd called her foolish yesterday?

Hmm. Should I read her? Mind reading was a bother first thing in the morning, but I couldn't exactly skip it. I clenched and unclenched my fists a few times, then concentrated on reading her thoughts.

'Anyone with manners ought to take care over their appearance before showing themselves. He wets his own hair every day and even dresses in a uniform, yet singles me out for criticism...! Last time, I let his unjust remarks sweep me along and failed to argue back, but today will be different. I shall teach this insolent whelp a lesson!'

Wow. She'd spent the whole day nursing what I'd said yesterday. How could someone so old be so petty? With a memory like that, she'd never have to worry about dementia.

I didn't know why her resentment had grown so much, but the feelings she'd pickled for a day had fermented into something else entirely. Meeting her head-on now would mean serious trouble. I'd better soothe her a little.

I answered as gently and sincerely as possible.

"No? Why would I object to you dressing up? It's a feast for my eyes."

"You wretch. Dressing properly is a basic courtesy in every land and age... What?"

"I'm human too. I'd much rather see a beautiful person dressed up than a wooden coffin floating around. Your colorful hairpin and clothes suit your pale complexion. Like an artist adding colors and flourishes to white paper. Those old stories about vampires having the magic to bewitch people must have come from somewhere."

"Huh?"

"The whole world would be jealous. You're an ageless, immortal vampire with an eternity ahead of you, so not even time can fade your looks. Perhaps staying inside your coffin would be a service to the world. Women would be spared their jealousy, and men their presumptuousness."

"W-well..."

She'd spent yesterday fuming as she dressed herself up. Coming out of her coffin meant she intended to become properly active again. The fine clothes and swept-up hair were a declaration of that intent.

Something prepared over a long time, with so much emotion invested in it, needed a fitting reward. Otherwise, it would all turn to bitter resentment and come crashing down on me.

In response to my praise, honed by years of back-alley swindling, the vampire tilted her parasol slightly.

"H-hmph. You do have a talent for empty flattery."

"I am flattering you, but I'm not lying. As you'll know if you've observed my usual words and actions, I mean every word I say. I actually can't say things I don't mean."

"Yet yesterday you called me foolish..."

"I said that because the situation was urgent. I never once said you weren't beautiful. You may not know this, but the Military State considers false reporting the gravest of sins, and saying that Trainee Tyrkanzyaka isn't beautiful would plainly be a false report."

Good. The vampire had finally fallen silent. She went far ahead without turning around, her face hidden behind her parasol, but a look at her thoughts told me she was quite pleased. Her opinion of me had improved a little, too.

Whew. Immediate crisis averted. Right. Time to fetch the Regressor.

The Regressor lived on the prison's first floor.

If you were wondering why the mighty Regressor still lived in a cramped, stifling cell when there were no instructors or other prisoners around, I'd tell you to lower your gaze and take a look.

She had "cut through" not only her own cell walls, but all the walls of ten adjoining rooms. The thick concrete walls, reinforced with steel plates to prevent prisoners from escaping, had been sliced into neat rectangles like flat-pack furniture and stacked carefully to one side. She used the resulting expanded cell as both a training ground and a home.

It was fair to call the entire first floor her house, and she apparently thought so too. The moment we set foot on it, a keen wariness turned toward us.

"Huh? Tyrkanzyaka? Azi? And..."

After identifying her visitors, she relaxed her guard. Even then, she grimaced slightly at the sight of me. How unfair. What had I done?

"Why are you here?"

"I have something important to tell you today. Come along."

"I'm busy. I've got things to do."

"Oh, for fuck's sake. You really can't play along, can you? Bet you were a loner outside."

"... What did you just say?"

She had been about to go back into her room, but poked her head out again, radiating hostility. Having brought the Regressor back with a single remark, I played innocent.

"I said I have important information to share, so attend my seminar and listen, Trainee Shei."

"This is important, so listen carefully. I. Don't. Have. Time."

'I got a feel for blood manipulation yesterday and have been swinging my sword all night. What a nuisance.'

Your dedication was admirable, but none of my concern. I lifted my chin and casually dropped something that might pique her interest.

"I'm going to explain the structure of Tantalus. You don't need that either?"

"The structure... of Tantalus?"

As expected, the lure of new "knowledge" she didn't possess made her rest a hand against her chin and think.

'I know something happens at Tantalus, but I still don't know much about its structure or secrets. If I learn how it's built, could I discover why "she" comes here?'

Over thirteen regressions, she had uncovered countless secrets and amassed a wealth of knowledge. What would happen in the future, what lurked behind the scenes in this world—few people alive at this moment would know more than she did.

The nature of regression meant that not even I, who could read minds, knew everything she knew.

But this was her first run visiting Tantalus before its collapse. In other words, I'd expected her not to know what I had learned about its structure during the Resistance attack. And I'd been right.

Outwardly, she hesitated, but I could tell she'd already been won over. I spun around and said,

"Well, even a margrave's position is no good if you don't want it. I'll be off, then."

"Wait."

She'd filtered that bit out.

Gamma—no, Wikrol—thank you. You must be dead by now, but I'll put your knowledge to good use. People leave their knowledge behind when they die, don't they?

"Wait while I get ready."

As the Regressor stepped behind a cloth partition into the inner room, Azi, who had been nosing curiously around the place, suddenly trotted over to me and dropped something from her mouth. It was a round orb of magically worked crystal, transparent, with a strange light swirling inside.

"Woof! Woof!"

"What? You want to play fetch? That doesn't mean you can just take other people's things."

It looked expensive at a glance. I carefully lifted the orb and examined it from every angle. What kind of orb was this? It seemed to hold quite a lot of mana. Was it expensive? Or dangerous?

"Oh, that? It's a bomb."

Both, then. I hastily hurled the orb far away.

"Aaaaaagh!"

The orb flew down the prison corridor. Meanwhile, I fled around the nearest corner and hid behind the wall. Damn it, how could she leave a bomb where a dog could get it? Explosives needed to be kept under strict control...

Wait. A dog?

With a sinking suspicion, I peeked around the wall. Just then, I saw Azi, who'd raced off into the distance, catch the falling orb with perfect form.

Ah. If she bit that thing, could it...

As I gaped, Azi's eyes met mine.

"Woof! Woof!"

"N-no! Don't go! Don't bite it! Don't come here!"

Terrified, I tried to spring up and flee. But by the time I had awkwardly begun to rise, Azi was already in front of me.

With bright, wide eyes, she dropped the orb at my feet. Before I could react, the bomb she'd released hit the floor. I collapsed into a crouch, flinging both hands out at random, as though I believed my hands and feet could stop an explosion.

And so the bomb landed on the corridor floor with a little bounce...

And I heard the Regressor snickering.

"Pfft, hehehe. Idiot!"

'Was he doing all that because he was scared? That's a Lava Tear! It will never explode unless you channel high-purity mana into it in a specific pattern!'

Utterly unchanged, the orb rolled over and bumped against my foot. I picked it up numbly and looked from it to the Regressor and back. At my utterly stupefied expression, she could no longer contain herself and burst out laughing.

"Pwahahaha! Come on, it's not like I'd leave something dangerous lying around!"

"... You said it was a bomb."

"It is a bomb. But it absolutely won't explode unless I try to set it off."

"If it's a bomb, it's dangerous! What the hell are you talking about? Did you drop your common sense into the bottomless pit when you moved in? Put it away right now!"

"Pfft. All right, all right."

Still chuckling, the Regressor picked up the orb. Azi watched her expectantly, but she simply tucked it into her subspace Pocket. Azi glared at her with the look of someone whose toy had been confiscated.

"Tsk."

I clicked my tongue and stood up. It felt as though I'd just experienced the limits of mind reading, and it left a bad taste in my mouth.

I couldn't read the knowledge the Regressor possessed from earlier runs until she consciously recalled it. That left me slow to respond to anything involving her, and made her reactions hard to predict. It was the first trial I'd faced in the one field where I took enormous pride: mind reading.

No, not even a trial. Honestly, wasn't regression a little outside the rules? My mind reading deserved praise for working so hard against an opponent like that. The world was unreasonable; mind reading wasn't lacking.

Anyway. Now that everyone was here, shall we go? After damaging my own image, adding anything more would have been foolish. I walked silently toward the fourth-floor management office, using only mind reading to keep track of what was happening behind me.

On the way, the vampire curled a hand in front of her mouth and smiled faintly.

"That was passable entertainment. We got to see him make quite a fuss. Still, frivolous though he may be, seeing him flee so disgracefully was rather disappointing. It was only a bomb."

"I wonder. From his reaction, I think he had some idea how powerful it was. If that bomb goes off, it devastates everything within a three-kilometer radius."

"Th-that much? Are they not merely used for fireworks displays?"

"It wouldn't be any use without that much destructive power. Heh. Anyway, it gave me quite a funny sight. Enough to make me want to preserve the memory."

The vampire quietly regarded the Regressor, whose mood had grown curiously light, then remarked,

"I have never seen you laugh before."

"Huh? Well, people laugh."

"It suits you. Why not smile from time to time?"

"From time to time? I..."

The Regressor suddenly fell silent and touched the corner of her mouth. Her face held the shock of someone who had just remembered something long forgotten.

'... I laughed?'

She had always striven to grow stronger. Struggled to gain even one more scrap of knowledge. Countless powers and secrets still slumbered in this world, and every second of her life was a struggle to obtain them.

Even here, trapped in the bottomless pit with nowhere to go, she never neglected her sword or her pursuit of power.

For someone like her, an emotional luxury like laughter was so unfamiliar.

'How long—no, how many runs has it been since I last laughed?'

With the strange feeling that an out-of-place breeze had brushed past her, and with longing for an emotion she'd felt so long ago, she brushed her fingertips over her mouth again and again.

As we continued in silence for a while, the vampire, seated comfortably atop her self-propelled coffin, shifted about as though something troubled her. Each movement made the silver hair falling beneath her hairpin sparkle in the lights and set her loose garments fluttering.

But the Regressor, deep in thought, gave no reaction at all. Finally growing impatient, the vampire decided to make a foolish fuss. Toying with her hair, she spoke.

"Ahem. Shei. Do you notice anything different?"

"Oh, right. Tyrkanzyaka. I realized something about blood manipulation during yesterday's fight, and I need your advice. Have a look once he's done talking."

"... Yes. I shall. It is good news that you have made progress."

Disappointed, the vampire slumped and looked back and forth between the Regressor and me, as though comparing us.

Good grief. She was being so foolish it was making me embarrassed for her. Maybe next time I just wouldn't compliment her.