For three days, nothing was heard from Mio.
It started with a cloud cost estimate. Makoto had accumulated a mountain of raw data from the days of its ongoing fight against scams. The text of posts, reported images, logs of the behavior accounts repeated night after night. Mio found herself wanting to have a smart tool read all of it, end to end. To have agents read it one item at a time, assign meaning, classify, summarize, and spin up stories by the mountainful: "Isn't this kind of scheme hiding in here?" It wasn't work the defenses strictly needed. It was closer to play. She wanted to turn a smart tool loose in the most interesting field of data in the world and let it gather meaning—that was all.
But running that huge volume of data through a frontier cloud LLM, one item at a time, changed things. The pay-per-token meter would keep spinning without rest. When she worked out a rough figure, it came to an amount that made your eyes pop.
"I can't bring myself to pay that much for analysis that isn't strictly necessary," Mio said, glancing at the estimate. "If I load the same volume onto the box at my place and run it there, the meter doesn't spin. The only outlay is electricity and my time."
Mikoshiba let the words "the box at my place" pass lightly. Later, he would come to regret that deeply.
After that, Mio stopped coming in to the office. There was a single message saying she'd just run it a little and take a peek, and after that, not even a read receipt. On the second day, the messages Mikoshiba sent were swallowed up with no reply. At noon on the third day, Mikoshiba made Aya stop her design work and all but forced her into the car.
"It's a welfare check," Mikoshiba said. "Her vital signs have been dark for three days. She might be so absorbed in analysis that she hasn't eaten and is slumped over her keyboard. This is part of labor management."
"Yes, yes," Aya replied in a flat monotone. "'Labor management' again today, huh. So, have you ever been to Mio's place?"
"No." Mikoshiba's finger twitched once on the steering wheel. "I know the address from her contract."
The moment he stood in front of the door, Mikoshiba took a step back.
A low drone was leaking out even into the shared hallway. The sound of hundreds of fans churning the air at once, like the inside of an airplane. The doorknob was faintly warm. On the other side of a single door, heat was breathing.
He rang the bell, but there was no answer. When Aya called her on her phone, the door finally opened a crack.
"...What."
Mio, peering out through the gap, was in a terrible state. Her hair had come undone and was scattered over her shoulders; there were dark circles under her eyes. The sleeves of her rumpled hoodie were pushed up to the elbows, and in one hand she held a can of energy drink. But her eyes alone were clear and sharp. The eyes of someone after an all-nighter, like the embers of the zone.
"I'm alive," Mio said. "What do you want?"
"Let us in," was all Mikoshiba said.
What lay beyond the open door was not a room.
It was a forest of graphics cards. Racks reaching to the ceiling formed walls, and on every shelf, bare GPUs were slotted in, several at a time. Countless fans spun at full tilt, and from the gaps where blue and green lights blinked, heat rose like a mirage. One whole wall was covered in monitors, and cables crawled across the floor like rivers. In the back, a squat box—an uninterruptible power supply, Mio would later say—kept up a low drone like a living thing. Through the open door, a wave of hot air came rolling out. Though it was September, the room was midsummer. No—it was the inside of a car parked under the blazing midsummer sun.
"...Mio," Aya said, standing frozen in the entryway. "This is a home?"
"It's a personal data center," Mio said, as though it were nothing. "If I ran this volume through a cloud LLM one item at a time, the billing meter would never stop. That kind of invoice isn't worth it for a hobby analysis. And no waiting on API limits. I don't like leaving my data in someone else's box, either. Load it all onto the GPUs at hand and run it myself. It eats electricity, but the meter doesn't spin. Nobody gets to peek. It's rational."
Besides, Mio said, tipping her can, "I only meant to take a peek. Before I knew it, three days had passed."
"Before rational, could you make it cool in here first?" Aya wiped the sweat from her forehead. "I've never seen anyone living in a sauna before."
Mikoshiba said nothing.
He took off his jacket and, sleeves rolled up, walked through the room. First he tracked down the remote for the wall air conditioner and lowered the set temperature by three degrees. Next he followed the rivers of cable across the floor, gathered the bundles that looked likely to trip someone, fastened them with zip ties, and made a single clear path. Then, out of the corner of his eye, he counted the empty cans and convenience-store bags piled up by the entryway, opened the kitchen fridge—saw that it held nothing but energy drinks and condiments—and quietly closed it.
"I'll go buy some things," was all Mikoshiba said.
"I don't really need anything," Mio answered, turning back to the monitors. "It's been running without problems for three days. Me and the box both."
"The box has," Mikoshiba said, putting his shoes back on in the entryway. "Your definition of 'running' is too loose."
Before the words were even out, he was already gone. He never spoke of doting. He just got there first and arranged things so she wouldn't be cold, wouldn't go hungry, wouldn't trip. With that pretense never cracking, the man called Ritsu moved.
Aya watched his back as he left and covered her mouth.
By the time Mikoshiba returned, Mio's analysis had reached a stopping point.
"It's finished one pass," Mio said, pointing at one of the monitors. Green text was streaming from top to bottom. "I had it read all the raw data stored in Makoto, end to end. In three days, it produced a mountain of 'discoveries.' 'Aren't the reports that spring up at night with this wording from the same gang using the same scheme?' 'Aren't the accounts with this behavior connected behind the scenes?' Countless plausible-sounding storylines."
"That's amazing," said Mikoshiba, who had come back carrying shopping bags, looking up at the wall of monitors. "All of that on this box?"
"It's not amazing. Most of it is garbage." Mio tipped her can. "A smart tool will hand you a plausible storyline even for pure coincidence. Show it noise and it'll read a story right into it. But most of the 'discoveries' born that way are nothing but pretty lines drawn through noise. An AI that mistakes coincidence for law ends up drowning while clutching garbage as treasure. Picking out the one real thread from the mountain of contrivances—that isn't the box's job. It's mine."
"I see. And you did that at home, of all places?"
"If I had a cloud LLM read this volume, the meter would spin up to an amount that'd make your eyes pop. With the GPUs at hand, it may breathe fire, but it costs only electricity and my time." Mio nodded her chin at the droning forest. "It's a matter of heat and the power bill. So I do it here."
Mio's finger stopped once at the corner of a monitor. The hand that had been sorting through the mountain of contrivances hesitated, suddenly, in front of one strangely neat cluster. The lines were too clean. Too uniform to be coincidence. Too coherent to be a contrivance.
But Mio didn't look at it for long. She tipped her can and looked away.
"Cut them all you want, there's no end to it, though."
It was a small, dry voice. To no one in particular, Mio set it aside behind her. That was enough play for today.