"Now. Down to business."
Once he had put the Othello set away, Mikoshiba laid a thin envelope on the desk. "I brought in our first meal ticket."
Inside the envelope was a request for consultation. When she saw the sender's name, Mio looked over at Aya.
"It came through me," Aya said. The lightness from a moment ago had drawn back a little. "He's an old acquaintance of my dad's. In Kamata—Ohata Tofu Shop. An old man pushing seventy who's kept that shop going with his own hands for over thirty years. Super stubborn, and a super good person. And lately, apparently, he's been drowning. He came to us grasping at straws."
Mikoshiba read out the main points of the request.
"'Our tofu doesn't keep, and yet on the same day we end up both making too much and throwing it out, and running out and missing sales. We do everything by decades' worth of shipping ledgers, and it just won't add up'—that's what it says."
Mio looked down at the shipping logs and inventory time series attached to the request.
The rows of numbers rearranged themselves into line graphs in her head, unbidden. The amount prepared. The amount sold. The amount left over. The amount short. They lined up along the axis of dates, rising and falling.
The moment she saw that waveform, Mio's fingers stopped.
Overproduction and stockouts. Two things that by rights shouldn't coexist on the same day were showing up regularly, like a pulse. This was tofu that didn't keep. If there was too much, there was nothing to do but throw it out that day; if there wasn't enough, the lost sales couldn't be made back. It was contradictory. And yet that contradiction had a strange regularity to it. A waveform that rose and fell at a steady rhythm, like an EKG.
"...Puzzling."
Mio's voice dropped slightly lower than usual.
"They go by the day of the week and it doesn't add up. And yet the way it's off has a pattern. If the data isn't lying, then the thing that's lying is—something else."
"Oh," Mikoshiba raised an eyebrow. "That's Himuro's having-fun face."
"By the way, Boss,"
Aya lowered her voice.
"There's one thing I want you to hear him out on. When old Mr. Ohata came to ask for help, he apparently kept saying it—that he'd had a right-hand man who took care of all the ordering and prep single-handedly. A craftsman named Tadokoro. And a little while ago, he got sick and died, just like that."
Aya's grip on the can tightened slightly.
"'Nothing like this ever happened once while he was around'—apparently he said it with tears in his eyes. The moment Tadokoro's 'feel' for it was gone, the shop ended up like this."
Mio said nothing.
A dead man's intuition. Information that could no longer be asked of the person himself. Missing data—no, something that had never been data in the first place.
—Ah. Oral tradition.
At her last job, too, the more important the system, the more likely it existed only in the head of the person who wrote it. "Don't worry, he understands all of it." Every time one of those hes quit, the whole company came down with amnesia.
Inside Mio, that one item alone blinked in a different color from the rest of the numbers.
"Anyway, let's have them show us the site once, tomorrow."
Mikoshiba stood up. "Day four, no money, and our first job. Himuro, can I count on you?"
"I have no reason to refuse. Not when the waveform is pulsing this beautifully."
Mio had already begun loading the logs from the request into her laptop. "Anything with a pattern always has an explanation. All that's left is to find it."
The next day, Kamata.
Ohata Tofu Shop was a cozy little tofu shop tucked behind the shopping street. In the tiled workroom, scooping tubs and stainless-steel molds stood in rows. In the sweet steam of soy milk that hung in the air, the owner, Ohata, stood planted with his thick arms folded. A sunburned, stubborn-looking profile. A sturdy back you would never guess belonged to a man pushing seventy.
"So you're the young folks who say you'll fix things with a machine."
Ohata looked Mio and Mikoshiba over, sizing them up.
"I'll tell you now, tofu is a living thing. How much water that day, how you put in the nigari—the hands remember all of it. You think a computer can understand that kind of thing?"
"It can't."
When Mio answered immediately, Ohata's eyes went wide. Beside her, Mikoshiba calmly took over.
"What my colleague means is this. What your hands remember, Mr. Ohata, a machine can't imitate. But—how you and Mr. Tadokoro made your judgments every day, a machine can read that from the 'results left behind afterward.' That's what we'd like to give back to you."
Ohata was silent for a while, then snorted. But he didn't send them away.
He had them bring out the ledgers in the back office, and when Mio started cross-checking them against the logs, a veteran worker washing beans in a corner of the workroom stopped what he was doing. A white-haired old man with a kindly look.
"Now, Tadokoro. That man went outside every single morning, without fail, and looked up at the sky. He'd check the day's weather and how cold it was, like this, with his skin. And then he'd adjust the amount of prep, just a little at a time, a pinch here and there. 'It's cold today, so a little extra of the scooped,' that kind of thing. —Never taught anybody, just did it all in his own head. So when he passed, that knack vanished, the whole of it."
Mio's finger came to a sudden stop on the page of the ledger.
Every morning, looking up at the sky. Adjusting a pinch here and there by the weather and the cold. —That wasn't written anywhere in the shipping logs. Not in the product codes, not in the dates, not in the quantities. It had existed only in the head of one craftsman who had died, and now it remained nowhere at all.
Mio gently stored that one remark somewhere separate from the other numbers.
Where it connected to the waveform, she couldn't see yet. But—just the sense that something might fit gave a faint tingle at the tips of her fingers.