"Hey, Boss."
Aya said it in a voice deliberately pitched to be overheard. In front of the coffee machine, standing right next to Mikoshiba.
"That's not a business decision, is it."
"What are you talking about?"
"The thing where you tried to peel Mio off me. All that about resources and traffic flow. That was all just jealousy, wasn't it." Aya poured coffee into a paper cup as she went on in a monotone. "When I get all cuddly with Mio, you get grumpy. I observed it three days in a row. My correlation isn't spurious."
Mikoshiba's expression didn't change in the least.
"It was a rational decision about resource allocation."
"A rational decision, huh."
"The CTO is the company's core asset. Protecting her concentration is the CEO's duty."
"Hmm. Impressive how far you can take that without using a single raw word like 'jealous' or 'keeping her to yourself.'" Aya drew her voice out with exaggerated slowness. "So? This 'duty' of yours includes going out of your way to wedge a chair in there. Admirable asset management."
"I believe I said it was optimizing the traffic flow." Mikoshiba didn't crack.
"Yes, yes, the traffic flow." Aya pushed the paper cup at him. "I'll go ahead and say every word you'd deny before you get to it. To the CEO who's only protecting his core asset—thanks for your hard work again today."
Mikoshiba took it and went back to his seat. He didn't crack. Not one millimeter.
Aya watched his back go—and didn't make a sound.
Only the corners of her mouth loosened, slightly. Just enough for a little puff of breath to escape. Everything else, she processed on the inside.
—Master Mikoshiba. Once again today, a most splendid display of possessiveness under the banner of resource allocation. That traffic flow, into which a chair was so deftly inserted—I, for one, bore full witness to it.
—And yet, the honorable CTO herself shows no sign whatsoever, in this lifetime, of realizing that she is the causal variable behind Master Mikoshiba's resource-allocation proposal. The master's three consecutive days of ill temper have not once been recorded in her detection logs.
—If I may be so bold, this one-sided love has once again been a perfect swing and a miss. I shall continue to observe from the front row.
As ever, Mio had no grasp whatsoever of the reason behind Aya's smirk. She was smiling in a good mood, probably because the chocolate had been tasty, Mio estimated. As posterior probabilities went, it was a reasonable enough line.
"So," Mio said, to no one in particular. "In the end, the true cause of my bugs is the all-nighters. If I sleep, they'll be fixed. Aya's doting is unrelated. Mikoshiba's concern is also unrelated."
She nodded, satisfied with her own logic. All-nighters were the cause, Aya was unrelated, and Mikoshiba was—part of resource allocation. The snacks, the chair placement, the reminders to hydrate, all of it was the CEO managing the health of an employee, and held no value beyond that. A very rational, explicable structure.
A model in which nearly every variable was correct, and only one had been fatally left out. Among the things she had classified as "unrelated," the real cause sat quietly. But what goes undetected is the same as what doesn't exist. At least on Mio's board.
"Moving on to the next problem." Mio had already turned back to her screen. "I want to bring Makoto's false positive rate down a little more. I'm moving the threshold."
Mikoshiba watched her profile for a little while. He started to say something and, as usual, swallowed it. On his desk, a cup of coffee he'd made went quietly cold, drunk by no one.
That night, while combing through logs to tighten the false positive rate, Mio's fingers suddenly stopped.
It wasn't a scam. No hype, either. Face matching, domain age, nothing caught—an entirely ordinary batch of ads. And yet—in the way the ad placements had been made, Mio sensed a small distortion.
On a board with only about a hundred and fifty people, during one particular time window alone, an inexplicable amount of ad spend had been scattered, thinly and evenly. Scattered less to show something to someone than to test something. An evenness like someone thinly measuring where her eyes would react and where they'd miss. Only in the movement of money was there a regularity, like human intent.
Mikoshiba hadn't noticed. He was full of the sense that the business had begun to run.
Only Mio, in a corner of the data, picked up that "smell of money" with her fingertips. A very small sense of something off, not yet even worth calling footsteps. She quietly wrote it in, a single line at the very bottom of her list of problems to solve.