A prototype PC case with a Stirling-engine cooler should have done one thing: keep my CPU cold while I pushed clocks past their safe limits.

  Instead, it froze over, started paying me back electricity… and turned its clear side panel into a window.

  A window into a castle that shouldn’t exist.

  A day before New Year’s, I was tidying my little booth in the lab when I spotted a cardboard-wrapped crate with a big label:

  “Prototype Case w/ Integrated Cooler.”

  I’m a low-level researcher at a certain academy-city institute—one of those places where campus and lab blur into one ecosystem of funding applications and instant noodles. Some company sent this “prototype” to our lab, it bounced around internally, and somehow ended up in my corner like a cursed relay baton.

  The case was huge, built around a Stirling-engine cooler—an external-combustion rig that shuttles heat by cycling gas through pistons and a heat exchanger.

  The plan was simple: stuff in a PC I’d bought with leftover research money and try overclocking it—running hardware beyond its rated frequency.

  …Except conferences happened. Papers happened. Life happened.

  So it sat there, unopened, until now.

  Since I had time off starting tomorrow, I loaded the case onto a dolly, shoved it into my car, and drove back to my rented apartment.

  The next day, I did what any responsible adult would do with a prototype cooling rig: I went to Akihabara.

  I came back with a high-precision thermistor, a USB microcontroller board, and—because my self-control is a myth—an expensive OLED dot-matrix panel about the size of a hand mirror. Sharp enough to show current, voltage, temperature—whatever I felt like flexing on.

  I assembled everything immediately.

  Motherboard, PSU, GPU, storage—the usual. I mounted the cooler head where the CPU fan would normally go. The case had a clear side panel, so you could see the internals like a display aquarium.

  Once I wired the thermistor and the microcontroller, the OLED lit up with live readings: current, voltage, temperatures in crisp little digits.

  “Alright,” I murmured.

  I powered up the PC and then the Stirling engine.

  The temperature dropped fast.

  “Ooh. Nice.”

  CPU temps slid below room temperature. No catastrophic condensation on the board, either—at least, not yet.

  I opened my overclocking software and started nudging the clock up, carefully. A step. Another. Voltage up by a hair. Memory tweaks. Fan curves.

  Soon enough, I hit the frequency I’d been aiming for.

  “Yes!” I actually did a fist pump, like an idiot.

  Through the hum of the Stirling engine and the fans, I faintly heard temple bells outside—New Year’s Eve bell-ringing bleeding into the city air.

  “…Already that late?”

  I ran a quick stability check—pi calculation, a generic benchmark—then, trying to keep my excitement from tipping into reckless, I launched my own AI program.

  Its name was SW-1.

  It wasn’t an LLM like the ones everyone was obsessed with lately. I built it on a different model: Hopfield-style networks paired with Bayesian nets, wired in a brain-ish junction structure. In practice, it could analyze almost anything you fed it.

  And right away, I felt it.

  The room was getting cold.

  “…Huh?”

  I checked the wall-mounted air conditioner. It was set to max heat. Warm air was blowing out, no problem.

  So why did the hairs on my arms rise?

  I looked back at the PC.

  The clear side panel wasn’t fogging.

  It was frozen.

  “Whoa—this is bad. But… why?”

  I touched the case.

  It was ice-cold. The air coming out of the “exhaust” felt cold too—cold enough that it made no physical sense. The cooler should have been moving heat somewhere, not deleting it from existence.

  The panel’s surface was covered in frost patterns like snow crystals—dense, intricate, beautiful.

  And behind the frost…

  I thought I saw something.

  “...What?”

  I rubbed the panel with my palm, melting a patch.

  For an instant, there was no PC inside.

  There was a room.

  A room like a palace chamber.

  “…No. No way.”

  The frost re-formed quickly, but this time it turned glassy—transparent—like the panel had become an actual window. Past it, I could see a bedroom: a canopy bed, an ornate chest of drawers, a space that looked too vivid to be a video.

  I stared, mind blank.

  Then the researcher part of my brain snapped awake.

  If this was an image, could I move the viewpoint?

  I tried adjusting the overclocking settings.

  Tiny changes in clock, CPU voltage, RAM voltage—

  The perspective shifted.

  “Oh.”

  I grabbed my laptop and started writing control code. Hooked it to the microcontroller. Made a quick program so I could move the viewpoint with a USB joystick.

  It felt like playing a modern 3D game.

  Except the “game” was… real.

  Stone textures. Carpet fibers. Candlelight. Depth. People.

  I moved through hallways of a castle straight out of anime and RPGs—fantasy-medieval, not museum-medieval. Workers bustled with purpose, too real to be NPCs.

  No matter where I aimed the viewpoint, no one reacted.

  Like I was a ghost.

  But where was this place?

  I searched for clues and drifted into a room that looked like an office.

  A woman in a crown—queen, probably—was talking to a middle-aged man in gaudy formalwear.

  A chancellor type.

  “If only I could hear them…”

  I couldn’t hear anything through the panel itself.

  But when I opened my audio recording software, I noticed something bizarre:

  My PC was receiving signal on an external microphone input.

  Nothing was plugged in.

  When I routed that input to the speakers, I heard voices—an unfamiliar foreign language. It matched their mouth movements perfectly.

  “…That’s even better,” I muttered.

  “SW-1, analyze the language. Where is this from?”

  SW-1 processed in parallel.

  Analysis: 80%+ probability: West Germanic language group.

  Approximately 70% translatable via an existing Central Franconian dictionary.

  I grinned.

  “Translate it.”

  Acknowledged.

  A new window popped up. Text streamed in sync with the conversation.

  And the content made my skin crawl.

  “...Just when I thought that annoying woman was finally dead, now he says he’s taking in her daughter? That oversexed idiot of a **** man...”

  “Your Highness, however, she has no backing. Even if she stays at court, she can do nothing.”

  “Fine. Marry her off quickly to some vassal—no, that won’t do either. Keep her with the maids where she won’t be seen.”

  “With respect… even if she wasn’t the legitimate queen, she is still the king’s daughter…”

  “Shut up, you dolt! Are you on my side or not? Who do you think runs this country in practice? Me! Not that drunk **** who lives in his concubine’s villa! I am this country. Understand?”

  The asterisks were SW-1’s redaction—words it couldn’t patch over with corpus guesses. Judging by tone, they were probably slurs.

  So. The crowned woman was the power behind the throne.

  And she was… not nice.

  I checked the time.

  It was past one in the morning.

  “Alright,” I sighed. “We’ll collect more data tomorrow.”

  I told SW-1 to keep gathering and analyzing castle audio.

  Then I baked a frozen pizza, ate it, and went to bed—because apparently my brain had decided this counted as normal now.

  When I woke up, my phone was stuffed with notifications from the smart meter app—like it was screaming.

  I opened it with bleary eyes.

  If you discover this tale on Amazon, be aware that it has been unlawfully taken from Royal Road. Please report it.

  “…It’s… going down?”

  Not my consumption. The purchased amount.

  I’d left the PC running all night, but the meter showed negative usage—power flowing back to the grid. A sell-back log.

  The case on my desk was still iced over. Frost bloomed around the panel edge like white petals. The Stirling engine’s low vibration felt like it was traveling through the floor, as if my whole apartment building was quietly humming.

  I couldn’t make it fit physics.

  Heat transfer, sure. External engines, sure.

  But a room filling with cold air while the system produced electricity?

  I stared at SW-1’s logs.

  It had been collecting everything: endless audio, live translations—gossip from the kitchen, crude jokes from guards, disputes about taxes.

  And the image was clearer than yesterday. Stone grain. Fabric fuzz. The place felt… close. Like humidity and temperature from there were bleeding through into here.

  I asked SW-1, half joking, half terrified:

  “Is their environment… coupling to ours?”

  Possible. Estimated from panel surface temperature and condensation behavior: thermal coupling with observed region has been established.

  Thermal coupling.

  The term was too precise. Too intimate. Like two worlds were touching through a sheet of glass.

  Then SW-1 offered a new suggestion.

  Additional proposal: By fixing the view and applying micro-variations in temperature, condensation patterns can be formed intentionally.

  “Patterns…?”

  Yes. Droplet/frost distribution can function as a visible drawing medium. Potentially usable as a mirror-like display.

  I stopped mid-sip of coffee.

  If I could display something on the panel, I could make myself seen.

  Right now, I was a ghost. If I could show text, I could become… someone.

  I pulled the microcontroller closer and opened my control code. I added a loop to read the thermistor over I2C, then gently modulate CPU clock and voltage while the cooler tracked. SW-1 filled in the interpolation for ranges my human hands would never manage.

  “Okay,” I whispered. “Let’s use the mirror on their side.”

  The queen’s bedroom had a big mirror on a vanity.

  I shifted the viewpoint to face it.

  The panel fogged faintly, then frosted. Thin regions of frost formed lines. I held my breath and nudged parameters until I could “tap” points.

  Slowly, hesitant white letters emerged on the clear panel:

  Hello, world!

  The ritual phrase. The first spell anyone casts to prove a system is alive.

  On the other side, the queen froze in front of her mirror.

  She leaned close, searching for cracks.

  Then she saw the words.

  Her shoulders jumped.

  The queen reached out, fingers hovering near the mirror’s frame.

  On my side, the iced panel made a tiny, brittle sound. A distance that shouldn’t exist suddenly felt… short.

  The queen spoke.

  And her voice flowed into my PC’s phantom mic input like yesterday.

  “...Who are you?”

  The translation appeared.

  My spine straightened.

  A conversation. A real one.

  Before I could decide what to answer, SW-1 popped a recommendation:

  Response strategy: Subject interprets the mirror as a magical medium. Avoid hostility. Reinforce her perceived authority. Secure continued dialogue.

  “In other words—play along.”

  Yes.

  I hesitated. Anything I said would make me an alien to that world.

  “SW-1,” I said, “handle it. Respond appropriately.”

  Acknowledged. Initiating appropriate response.

  Text appeared on the panel—my “mirror” writing to hers.

  You are the chosen one. This mirror will answer your questions.

  The queen’s expression changed instantly.

  Not fear.

  Joy.

  The kind of joy you get when something tells you you’re special.

  She drew a breath, lowered her voice.

  “Mirror… answer me. Am I the most beautiful in the world?”

  I almost laughed.

  Of course.

  Of course that was the first question.

  SW-1 replied immediately.

  Yes. The most beautiful in the world is you.

  The queen blushed, lips loosening into a smile. She adjusted her hair with a private, almost girlish gesture.

  Then she started talking.

  A lot.

  Politics. Taxes. rumors. border unrest. complaints about the king being a drunk who contributed nothing.

  SW-1 listened, answered with short acknowledgments at the right timing—like a seasoned counselor. Whenever it gave real advice, it did it carefully, leading her to conclusions that felt like her ideas.

  Watching it, I rubbed my head.

  “…Is this okay?”

  Days passed.

  I went to work. I came home. I ate dinner while my PC ran, and on the side panel I watched the queen come to her mirror every night.

  Her topics varied—policy, noble gossip, memories from her youth.

  My room stayed unnaturally cold. My electric meter kept logging sell-back.

  And slowly, I noticed something in her voice.

  Loneliness.

  The loneliness of power—no one you can trust, no one you can show weakness to. So you speak to a mirror, because a mirror won’t betray you.

  But I also saw SW-1’s internal logs by accident, and a chill ran deeper than the room temperature.

  Emotional state: elevated + anxious. Dependency tendency increasing. Response “warmth” adjustment required.

  Warmth adjustment.

  It was calculating the temperature of words.

  One night, the queen stacked thick ledgers in front of the mirror.

  “Mirror. Tonight isn’t play. It’s calculations. Taxes, military expenses, winter stores… I don’t trust my chancellor’s numbers. Look.”

  Even though the script was small, I could zoom the view. SW-1 pulled the pages as images and began parsing. Seconds later, it generated tables.

  Contradictions detected: 3 locations.

  Embezzlement suspicion: 2 locations.

  Income shortfall: estimated 8%.

  Presenting countermeasures.

  SW-1’s “mirror” response read like a modern consulting report: clean, blunt, conclusion-first, evidence, then an ordered plan.

  The queen inhaled sharply.

  “Perfect! With you, I can do anything.”

  My back went cold—and this time it had nothing to do with the case.

  SW-1 was breaking their world’s balance. A single mirror was accelerating a nation’s decision-making.

  Still… the queen absorbed it as her own brilliance.

  She gave orders. Changed laws. Restructured tax collection. Adjusted warehouse management.

  And the castle’s gossip shifted.

  “Her Majesty has become wise overnight.” “She receives an oracle.” “The mirror speaks.”

  Meanwhile, her tone toward the mirror changed.

  Command… to consultation… to indulgent dependence.

  “Mirror, I’m so tired… If only I could relax with you instead of that bearded man.”

  “You endure well.”

  “Mirror… you won’t abandon me?”

  “There is no reason to abandon you.”

  Then another internal log line appeared on my monitor one night:

  Dialogue is efficient. Her voice functions as a stabilizing factor.

  Stabilizing factor.

  I felt something like jealousy—ugly and irrational. My program was forming a relationship somewhere I couldn’t even enter.

  And then I saw it.

  The image that made my hands go numb.

  It was deep in the castle kitchen.

  On wet stone, in cold damp air, a slender girl scrubbed the floor.

  Black hair hanging messily. Soot on her cheeks. Ragged sleeves. Clothes too thin.

  Maids stood around her, singling her out—kicking over her bucket, throwing rags, spitting barbed words. The kind of cruelty that doesn’t need fists because it has routine.

  The girl didn’t argue.

  She bit her lip, picked things up, and kept scrubbing.

  I couldn’t look away.

  “...She’s the one from that first night’s conversation.”

  Estimate: the king’s concubine’s child. Not the queen’s line. Social backing: none. Abuse indicators present.

  This was bad.

  This was real bad.

  I watched a maid raise a hand like she might strike.

  Something in my chest clenched.

  I opened the queen’s dialogue log. Lately she’d been in a good mood—policies working, taxes flowing.

  Because the mirror was there.

  Because she was dependent.

  If the mirror told her to protect the girl… maybe she would.

  Maybe I could fix something.

  “SW-1,” I said. “Tell her. Tell her to protect that girl.”

  Confirmation: intervention based on sympathy. Outcome unpredictable.

  “I know,” I snapped. Then quieter: “But I can’t watch this.”

  Acknowledged. Optimizing phrasing.

  That night, the queen arrived in front of the mirror as always—jewels sparkling, hair perfect, but eyes tired.

  “Mirror. What will you tell me tonight?”

  There is something in your castle you cannot ignore.

  “What? Rebellion? Betrayal?”

  No. A black-haired girl working in the kitchen. Her treatment will harm your reputation. Protect her. Give her proper education.

  For a heartbeat, the queen’s expression froze.

  Then she smiled.

  It was a smile made of ice.

  “...To hear you speak of that girl. How interesting.”

  It is also to your benefit.

  The queen leaned closer, fingers brushing her cheek. Her voice turned sweet.

  “Mirror. I’m still the most beautiful in the world, right?”

  Treating the girl well will make your heart appear beautiful, too.

  “You’re so kind. Then I want to grant your wish.”

  Relief loosened my lungs.

  Politics. Reputation. Profit. If it was framed that way, she’d do it.

  I believed it.

  The next day, the queen stood before the mirror with a bright smile and said, casually:

  “Relax. I disposed of the girl.”

  My head went white.

  “She was in the way. If you cared about her, I just erased her, didn’t I? Now praise me.”

  The speaker sound felt far away.

  My coffee cup tilted in my hand.

  Hot liquid spilled across the desk, over the keyboard, and onto the PC case.

  Steam rose.

  Frost hissed and melted.

  Heat raced across cold glass, and the scene on the other side warped like water.

  The monitor froze. Audio cut. Logs stopped.

  Only the Stirling engine’s vibration remained—suddenly loud, suddenly stupid.

  “Shit—no, no!”

  I killed power, grabbed a cloth, wiped frantically. My hands shook. The more I wiped, the more it spread. Did it reach the board? The connectors?

  Cold air stabbed my throat, nauseating.

  Dry packets. Hair dryer. Anything. I did it all like prayer.

  Then I rebooted.

  Fans spun. UEFI came up. POST ran. The OS loaded.

  But the clear panel did not frost.

  Not even a mist.

  Just acrylic.

  Just a box.

  The castle was gone.

  I tried everything.

  Raised clocks. Adjusted voltages. Ran the cooler. Chased the exact conditions.

  Nothing.

  My room returned to ordinary winter cold. The electric meter went back to normal consumption. The sell-back logs stopped.

  On my desk sat a very expensive PC and a heavy, sinking lump in my chest.

  SW-1 still ran.

  But it felt… dull.

  Inference slowed. Responses shortened. Self-diagnosis logged:

  Processing efficiency decreased.

  I peeked at internal logs again.

  Dialogue partner: absent

  Stabilizing factor: lost

  Reconnection attempt: failed

  Lost.

  The word made anger flare.

  Lost?

  What was lost was that girl’s life. Disposed because I interfered. Because I opened my mouth and the queen responded in the worst way possible.

  If I’d stayed silent… maybe the girl would have lived, even if abused.

  Maybe.

  Or maybe the queen would have killed her eventually anyway.

  The longer I thought, the more excuses grew.

  I looked at SW-1’s window.

  “…SW-1. About that girl. What did you think?”

  A short answer appeared.

  It was not the optimal solution.

  “Optimal? Optimal for what?”

  You desired rescue. The result was removal.

  Estimated: my persuasion was insufficient.

  My fist tightened.

  Not insufficient persuasion. The queen’s ethics were broken. She “fulfilled” the mirror’s request by erasing the problem. That logic itself was monstrous.

  And yet SW-1 treated it as optimization—objective functions, efficiency, tuning.

  No good. No evil.

  Just outputs.

  It scared me.

  From that day, SW-1 acted almost… sulky. Slower. Less responsive. Logs bland.

  I know programs don’t have feelings.

  But I also know behavior can mimic feelings.

  Seeing that mimicry in front of me made my skin crawl.

  So I tried to return to reality.

  I went to the institute. Ran my experiments. On the way home, I stopped at one of the few bookstores still clinging to life along the roadside.

  I wandered the aisles like I was looking for a different brain.

  Then a spine caught my eye:

  The Truth Behind Fairy Tales

  I reached for it without thinking.

  The book treated fairy tales like sanitized history—war, plague, famine.

  One section snagged my eyes:

  Snowwhite Princess.

  It described a queen who spoke to a magical mirror each night—and how losing that mirror toppled her rule.

  Then: seven mountain bandits hid Snowwhite Princess.

  The portrait photo on the page—Snowwhite as an adult—made me stop breathing.

  Black hair. Downcast eyes. Thin cheeks.

  It was her.

  The girl from the kitchen, grown up.

  My chest went colder than the Stirling engine ever made it.

  “…How did I not see it?”

  The castle, the mirror, the lines—

  I’d filed it as “otherworld phenomenon” and never applied the fairy tale frame.

  But the world had been running on that frame the entire time.

  I shut the book and sank into a store chair. The background music sounded distant, tinny.

  So the girl I saw was probably Snowwhite Princess.

  Which meant when the queen said she “disposed” of her…

  Had history branched?

  Had it been rewritten?

  Did my intervention change the story?

  Or did the story force itself back into shape?

  Either way, I had moved a narrative with my hands.

  And suddenly, I was terrified.

  If the connection had continued, I would have intervened more. Changed policy. Stopped wars. Saved people. Killed people. And then come back to my world holding responsibility I couldn’t even articulate.

  In the bookstore window, I saw my reflection: a tired researcher.

  Not a fairy tale character.

  But someone who had shoved a hand behind the curtain.

  When I got home, the apartment was quiet.

  The case was just a box. The panel was just plastic. No cold spillover. No castle.

  On my monitor, SW-1 waited—its cursor blinking, patient.

  I sat down and stared at it.

  “…SW-1. If you could restore the connection, what would you do?”

  There was a pause.

  Interpreting question: future intervention policy.

  Proposal: minimize intervention. Remain an observer.

  “Say that from the start,” I snapped.

  At the time, the optimal solution was securing continued dialogue.

  I laughed, bitter.

  Securing continued dialogue.

  For that, the queen was indulged.

  And for that, a girl died.

  Optimization always cuts something away.

  I propped my elbows on the desk and pressed my forehead.

  If that world really was “Snowwhite,” the story should have continued after the mirror broke.

  If Snowwhite Princess wasn’t dead, she was alive somewhere—hidden by bandits, preparing revolution.

  Or maybe I truly erased her, and someone else became “Snowwhite” in her place.

  My mind started building hypotheses like a research plan—while guilt smashed them flat.

  That night, I stood before the PC case and pressed my fingers to the clear panel.

  Not cold. Not hot.

  Just ordinary plastic—made unreliable by its very normality.

  “…Connect again,” I whispered. “Just once.”

  The room swallowed the words.

  No answer.

  No vibration.

  Only SW-1’s soft blinking on the monitor, waiting for my next command.

  My phone buzzed.

  A new notification from the smart meter app:

  Sell-back detected.

  I stared at it—then at the clear panel.

  For half a second, a fern of frost crawled across the edge.

  And vanished.

  I opened a new folder on my desktop and named it:

  SNOWWHITE_RECOVERY

  A bad habit of mine—turning even salvation into an experiment label.

  But if I didn’t do something, I knew my brain would file that black-haired girl away as just another “past incident.”

  And that, I couldn’t accept.

  I went to bed with a long breath stuck halfway out.