Seto only meant to optimize the afterlife's defenses.
One week should be enough to modernize an entire military, retrain the guards, and eliminate every inefficiency.
As for making Atem fall for him?
That was simply another item on the checklist.
This is a translation of an original work on Pixiv.
Original Title: 文明加速装置
Original Author: 葉人(@Hathor₋yuki)
Personal site: https://prideshipping.sakura.ne.jp
"I've been busy lately with reinforcing and maintaining security."
Atem said it while adjusting his deck.
Hearing that, Seto laughed inwardly, careful not to let it show.
"…Military affairs, hm."
"Hm?"
"Unacceptable, that something like that should eat into your time. I'll have it handled immediately."
"What?"
Seto Corporation was, these days, an amusement company and various other things — but its predecessor had been a merchant of death. Seto carried the shadow of the arms industry firmly on his back, and he knew it.
In fact, he'd say outright that war was foolish, and mean it — while making no particular effort to hide his own history in it.
There was no separating himself from it. It functioned too well as deterrence, as leverage, as a means of bringing the world to heel.
"Atem. Show me the documents."
"You'll actually understand them just by looking?"
"I will. I picked up hieroglyphs during the archaeological digs. Somehow I can even read ancient priestly script."
"Why…"
There's no way he could misuse it, Atem figured, and handed over part of the documents.
Seto skimmed through them at speed, instantly assessing the terrain, the ancient security measures, military structure, resources, personnel.
For a mind as absurdly overbuilt as Seto's, cutting the waste and optimizing took no time at all.
He was, after all, a specialist in death from a far more advanced era.
Seto flipped through it all and let out a short laugh.
"A week will do it."
"You — are you actually serious?"
"Have I ever not been?"
"No… well, I'm not letting you do that."
But inside Seto's head, the finished blueprint — and the method to get there — was already being assembled, piece by piece.
Reinforce things in a way that looked natural to ancient people. Train them. Improve the defensive layout.
Modern technology and management methods could be introduced quietly, wherever they were needed, without drawing attention. In that regard, Seto was, thoroughly, a creature of pure rationality.
And a creature of pure follow-through, too. He said what he'd do, and he did it.
"You made the mistake of letting it slip to a professional. Give up."
"Professional — you?"
"Until a few years ago."
"Ah. Right. I suppose so."
"That's how it is."
"But you don't want to get dragged into this again, do you."
This was a man who'd blown up Alcatraz, a monument to the arms industry, without a second thought.
"No issue. This world isn't going to produce any more corpses at this point."
"You don't have to put it like that."
"I'll come next week. And while I'm at it, I'll have you falling for me too."
"…Hm?"
Falling for him? Some new joke trending in the living world, maybe.
He didn't seem like the type interested in that sort of thing.
A hand was held out, so Atem handed over more documents.
Seto looked them over and then looked at Atem.
"This — don't tell me you're counted as part of the fighting force too?"
"Not exactly assigned, but I figure I'd be useful in an emergency."
"…Should I retrain you from scratch?"
"Ha, funny."
"I don't joke. Either drop off the headcount or get retrained. I have no use for you in the army I'm building. Make that known."
Saying that, he left for the living world, taking every last document with him.
Day 1.
The following week, the self-proclaimed specialist showed up carrying an armful of things Atem couldn't identify.
"What's this?"
"This world's combat is fundamentally direct physical confrontation, correct? Demonstrating the basic forms through holographic projection will be more efficient than verbal explanation—"
"Wait, wait, wait. You're actually going through with this?"
"I'm clearing this quickly to free up your time, which I intend to allocate to myself. What's your weapon of choice?"
"I can use most weapons — no, wait, that's not the point, everyone has their own pace, there's a process to—"
He'd known perfectly well the man followed through on everything he said.
And the displays already deployed around him were showing the map of the afterlife Atem had handed over, annotated here and there. In hieroglyphs, courteously enough.
Seto, brimming with motivation, and Atem, still visibly reluctant —
"Gather the department heads."
— came the order.
As usual, it was unclear which of them was actually king here.
"If you just tell me, I'll do it myself."
"Scribes? I'll have the documents copied. Show video footage for now to the ones counted as troops — already generated."
Too well prepared. Suspiciously so.
"Which documents, exactly?"
He pointed to several of the deployed displays.
Curious what they said, Atem found a list of proposed changes from the current setup. Well — that much was manageable.
Atem decided to let him handle the smaller changes to keep him satisfied, and quietly finesse the rest.
Seto was giving instructions to the gathered department heads. The one man in modern clothing, standing there as if it were the most natural thing in the world, giving directions with practiced ease — it made for an especially surreal scene.
After distributing equipment along with a round of instructions and sending everyone off to their posts, Seto came back to where Atem was.
"While we have the time, Atem — your test."
"Test?"
"I'll be your opponent. You said you had no particular weapon of choice — use one if you want."
"There's no way I can go around punching or kicking you."
"Of course you can't do it accidentally. That's why I said I'd be your opponent. In your preferred phrasing: 'come at me with everything you've got.'"
This guy. Mocking me.
Provoked by his own words thrown back at him, Atem took the bait.
"Come on then. The training ground's this way."
They trained a few times a week, and Atem was reasonably quick on his feet.
Against some tech-obsessed modern man…
He'd gotten irritated enough to think he might actually land a hit — but he ended up being toyed with entirely, without landing a single one.
"Well, about what I expected. Fail. You're cut."
"Hah — you… hah…"
"Winded already, from that?"
"Hah— because— the difference in build— is a factor—"
"As expected, you're quick, at least."
"Well, thanks so much!"
Being complimented didn't feel great given the circumstances.
This guy was this strong? No — wait, isn't modern martial arts basically cheating at this point?
"The king proceeds as planned in the direction of retreat."
Whatever Seto thought a king was, it definitely wasn't the standard idea of one. No respect whatsoever.
Come to think of it, this was a man who'd sacrifice a god without blinking, so maybe it made sense.
Right after a match, he had the nerve to look completely composed, opening up another display and doing something with a flick of his fingers.
"I don't fight as a rule, but I should have the training instructor increase the frequency starting tomorrow…"
"That's just maintaining the current schedule — cut the time down and it defeats the purpose. I'm changing the content. Already relayed to the department head."
Doing whatever he wants.
But given his earlier declaration about "falling," Atem had already lost, decisively.
"You saying you'd have me falling — this is what you meant?"
"What are you talking about."
Seto looked at Atem, genuinely puzzled.
Did he forget? Who was the one who made that weird joke.
A hand was offered to Atem, still sitting on the ground. He considered swatting it away, but that would've looked like sulking, so he let it go.
Atem was hauled up by the arm.
Seto checked off one of the displays, closing it out.
Day 1: Observing psychological distance
Day 2.
The one with the incomprehensible combat ability had apparently been issuing orders in every direction since morning.
A voice was audible from the next room.
He'd handed out communication devices, so that was probably it.
Atem was checking military maintenance records on a tablet.
For someone who called himself a specialist, there wasn't a single loose end or gap to find. Atem searched like it was a puzzle, assuming a low-tier villain as the player — but there genuinely wasn't an exploitable hole anywhere.
Giving up the search, Atem sighed and left the room.
And ran straight into Seto, buried in displays again.
Somehow managing to walk while tapping and writing across the screens with his fingers. Walking while texting, basically.
"Heading somewhere?"
"I intend to see the elite troops and the weapons in person, at least."
"It's only one week, you know."
"That's enough. Continue the drills afterward."
Different from during a duel, he was steady, calm the whole way through.
Calm — in ordinary conversation this man leaned quiet, come to think of it. Their old friends had always been the loud ones.
Making his rounds through the military-related departments, Seto once again gave directions and instructions with practiced ease.
His expression was serious throughout, and it was clear he genuinely intended to improve the afterlife's military standing.
Their eyes met briefly at one point — he offered a light smile, then moved on to the next department.
That smile was gentle, and it stirred something in Atem's chest without his permission.
Seto, once again, checked off one of the displays and closed it out.
Day 2: Contact
Day 3.
Today was training day.
As usual, Atem headed to the training grounds.
"Why are you here."
"Just finished instructing your department head. Perfect timing — let's go, come on."
"We already did this."
"I'm relaying the weak points for further coaching."
"I'll get that coaching in due time."
"You— whose kingdom is this. Do you even have any drive."
Whoa, the president's voice just got serious.
The card game side of him was supposed to be the intense one, but Atem still wasn't used to work-mode Seto.
"Ugh, fine, fine. I'll do it."
He'd expected to get thoroughly beaten again, but instead got put through drill after drill — move like this, react like that. Not beaten, but exhausted regardless.
"Your movement's still good, as always. Keep training and you'll manage basic self-defense at least."
Being complimented still didn't feel great given the situation.
"Want a gun, at least?"
"I'm not you."
"I see."
Guns held no fond memories for him.
He'd been shot at as a warning on the very first day Seto invaded the afterlife — that had taught him a lesson. And Seto's voice back then had been dead serious too.
"You. What happened to our endless road of battle, stretching to the horizon."
That much must have mattered a great deal to him, terrible as it was. It mattered to Atem too, if he was honest — but he was still holding onto some resentment, so he set that aside.
Now, though — how did things stand? They were just playing a normal game.
Seto's voice carried well, so their exchanges tended to be loud and dramatic in the usual way, but there was no shouting fueled by anger this time.
No arguing about past or future, about values, either.
Seto watched Atem's reactions and tapped a checklist item. Praise laced with provocation. Quietly making him conscious of being evaluated, without him noticing.
Day 3: Praise, light provocation
Day 4.
By this point Atem had more or less adjusted to Seto-style afterlife renovation.
Everyone had simply accepted the holograms as normal, contacting Seto directly or asking questions when something confused them.
The head of the Seto school himself responded to every single one, personally.
He's actually really attentive.
Whenever their eyes met, Seto offered a light smile.
His expression wasn't exactly soft, but his manner lately hadn't been as harsh as usual, either.
Atem had more or less given up trying to figure any of it out, so he waved lightly and sighed.
Seto's presence was distinct enough that whenever he was around, Atem's eyes wandered toward him without meaning to.
Atem tracked Seto with his gaze, unconsciously, again and again.
Noting that, Seto checked off the fourth item. Gradually shifting Atem's heart to center on him.
Day 4: Psychological manipulation via smiling
Day 5.
The meaning of what was written made no sense.
Was there no equivalent term in the ancient language, or did it simply not make sense at all?
Atem went looking for the man who was probably walking around with displays deployed all over his body.
A guy who looked like a walking Christmas tree — there was probably only one of those in this world, maybe even in the living world. He was easy to find.
"Kaiba."
"What is it?"
Called out to, the deployed displays parted, and there he was.
Moving around everywhere all day, and yet his stamina held up remarkably well. Not a trace of fatigue anywhere. A monster of stamina.
"This — what does it mean in modern terms?"
"Ah, that. Open this tab, and the annotation appears."
Tapping the small red triangle brought up the details. There genuinely hadn't been an equivalent term, so it had been summarized in modern language instead.
Something Atem had noticed recently — this man was good at explaining things. Reading it through, he understood immediately.
"This is a detail only you'd need to know, but I'll translate it if it's useful."
Just from the documents Atem had handed over that one time, Seto seemed to understand the circumstances of this entire world remarkably well. As always — sharp.
"No, I got it. Thanks."
Every time understanding clicked, Atem's trust tilted a little further toward Seto.
Not through words, but through action — a sense of his heart being taken hold of, quietly.
"Any other questions?"
"Just this one, for now."
"Come find me anytime."
Saying that, Seto turned back into a Christmas tree of displays and walked off toward the guards' training grounds.
From among his own Christmas ornaments, Seto checked off the fifth item.
Day 5: Small follow-ups to build trust
Day 6.
the afterlife's military situation had reached the point of pure execution.
Everything that had been communicated and drilled these past few days would transition today, with full operation beginning tomorrow.
It had only been a matter of days — Atem had assumed it would settle for something like a rearranged security layout, but the Minister of Defense had touched everything and finished it all.
Fast as ever.
"Atem. The proclamation."
"……."
"What."
"Just — being ordered around by my own Minister of Defense, is all."
"I never recall becoming one of those. The army answers to me, but the king is you."
Truly — it was unclear who the king actually was here. At the very least, Seto absolutely did not consider himself one.
Honestly, someone spare a thought for the person actually being dragged around by all this.
"I'll go handle it."
Atem gathered the department heads in the throne room and issued the royal decree on the changes.
Seto watched the whole thing.
"Atem."
Seto caught him as he returned.
"What are you making me do this time?"
"…No — I was thinking it was about time for you to fall."
What is he talking about — and then it clicked. That living-world joke again.
Had that declaration actually been serious? If so, it made no sense.
There'd been no sweet words whispered, nothing to build that kind of mood.
"Hold on. This entire week, both of us have done nothing but work — how does that lead to this."
"This week, you've done well, admittedly."
Still talking down to me, as usual.
Trust in this matter had built up enough that it didn't spark anger. Exasperation, sure.
"You've worked hard too, you know?"
"It's to free up time — time to allocate to you."
Right. That's how this started.
And then the living-world joke had gotten tacked onto it. It was a joke, right?
This entire week, Seto hadn't shown a single hint of that intention.
And yet not once had his words ever been anything less than serious.
"That was a joke, right?"
"What was? I'm heading back to my room."
Back in his room, Seto touched the checklist once again.
He's probably beginning to grasp, gradually, that I'm serious.
Day 6: Deepening awareness
Day 7.
"Military maintenance complete. Security and defense systems fully optimized."
He'd apparently installed a monitoring system at some point, checking the new structure from within his cluster of displays.
He actually did it. He really did it.
That was Atem's honest reaction.
The whole thing had started as just rearranging security placements.
"Something like a camera, in this world…"
"Better than a drone."
"That's true, but."
The world this man existed in advanced dramatically, wherever he went. The living world, and now this afterlife too.
Atem decided to name Seto Kaiba the Civilization Accelerator.
If such a device existed, it was undoubtedly him. More occult than the Millennium Items themselves, arguably.
Filed under "occult," the two of them were basically the same category.
The same as him, huh.
Thanks to the run-through the day before, or because the plan had been flawless to begin with — probably both — there was nothing left to adjust.
"Atem, this."
He pointed at a display reading: Day 7: Make him fall.
So it really wasn't a joke after all.
Whether it counted as romantic love, Atem couldn't say. But he understood, at least, that it was only a matter of time.
Because his heart had already opened.
"You didn't have to rush it into a week…"
"If you're going to fall eventually, when it happens doesn't matter, does it."
"'Eventually,' he says."
Looking at the result, he supposed it didn't matter. Whether to be exasperated or impressed, Atem genuinely couldn't decide.
Wearing something like a resigned smile, Atem checked the box himself with his own finger.
"A week, just as promised."
Seto's expression settled into something satisfied.
At that moment, Atem felt something bittersweet stir in his chest.
Day 7: Make him fall
The Civilization Accelerator works on hearts, too.
Atem's world was never going back to what it was.
