Three weeks had passed since the fraud ring was busted.
The map Mio had drawn—ad placement accounts, disposable domains, payments, bank accounts, and the flow of money circulating among them—had become the grounds for the police to kick down the doors. Starting from the withdrawal runners they picked up, they traced one link to the next, and several scam call centers in Japan were shut down. A modest headline ran in the city pages of the newspaper, but Mio didn't read it. The bust wasn't her territory. The moment she handed over the map, her work was done.
So it made sense, looking back, that the one who carried the follow-up report to Mio's desk was not the police but Aya.
"Mio. Have you seen this?"
It was early afternoon. Aya slid a tablet onto the desk. The breaking-news screen of a news app. Mikoshiba, too, had at some point come to stand behind Mio, peering at the screen. Mio was holding a canned coffee she'd just bought from the vending machine, still unopened.
It said it was a follow-up on the fraud ring bust. As analysis of the seized devices progressed, records had been found, on the seized devices' end, showing that the scam ring had regularly been buying a "sucker list"—who was vulnerable to what kind of ad—from an outside "vendor." According to sources close to the investigation, police had searched the premises of a corporation believed to be that "vendor." That was what the article reported, flatly.
Mio read the article to the end. She hardly needed to. The moment those words, "sucker list," appeared, the answer had half come into focus. But when the name of the selling corporation entered her eyes as written letters, it took on a different weight.
Kotoba Inc.
Mio's old stomping ground.
"As a mechanism, it's just what I inferred back then—when I saw how 'too perfect' the damage was."
After handing the tablet back to Aya, Mio explained it to Mikoshiba and Aya at her own seat, matter-of-factly. Her voice carried no particular emotion.
"The detection engine I wrote before was still sitting on Kotoba's servers. Who's vulnerable to scam ads—a judgment for picking out the people who need protecting, saying 'protect this person.' Flip it, and it becomes, exactly, 'hunt this person.' A list of people to protect turns into a list of marks to deceive. Same data, same model, only the direction reversed."
As she spoke, Mio felt the sticky note she'd never been able to peel off fall from her fingertips. The reason Kotoba's town square was too clean, even without a gatekeeper. It wasn't integrity. If you turn the marks into a list and sell it, the scam ring doesn't need to scatter ads indiscriminately across the square. They can pick off the people on the list from outside the square—with cloaking, luring them to LINE. That was why only the square was so unnaturally clean. So the "Zero Scam Ads" sign had been the worst kind of cleanliness there is.
"So," Mikoshiba said quietly. "Kotoba was selling that to scam rings."
"Reading the article, that's what it comes to." Mio shook her head. "But just because Kotoba's list was found in the scam ring's hands doesn't necessarily mean Kotoba sold it. It may simply have been a data leak."
Mio set the canned coffee, still unopened, on the desk.
"So to prove they sold the list, you need someone on the inside willing to cooperate."
The decisive evidence to break through the wall could only be obtained from inside. But someone so admirable as to hand over their own company's crimes, with their own hands, to the outside—where in today's Kotoba would such a person be? Mio held almost no hope for that line.
A few days later.
"There's a visitor who says they want to see you," Mikoshiba said, lowering his voice in front of the door to the reception area. "Someone from Kotoba, apparently. When I heard the name they gave at the front desk, I figured it was probably about you."
When Mio entered the reception area, a man rose slowly from the sofa. Seeing his face, Mio's eyes widened slightly. It was rare for her expression to move with emotion.
"...Mr. Shiina."
Sixty-three years old. The head of Kotoba's development division. The Founder's right-hand man. The former boss who, alone in the company, had properly gauged the skill of Mio, who had neither academic credentials nor title, and given her production environment access and freedom.
And—in that conference room where Mio was fired. The man who had taken the brunt of Kiryu's fury—"Why give a high school graduate access?"—had been saddled with "supervisory responsibility," and had been demoted and shunted off into a dead-end post. The man who, that day, had moved his lips to defend Mio, but couldn't make a sound, and had lowered his eyes.
Shiina looked much older. In just over three years, could a person's hair go so much whiter? Mio thought, irrelevantly.
"It's been a while, Himuro." Shiina bowed his head deeply. "—You probably know about the matter, since it's been in the news."
Shiina looked straight at Mio. "...I was the one who reported it to the police."
Mio said nothing.
"The access logs, copies of the contracts, records of the money transfers. I took them all out and delivered them to the police. President Kiryu has been signing off on selling the code you left behind and our users' data to outside parties, calling it a 'data business.' I watched it up close for years. Unable to raise my voice."
Shiina's voice trembled slightly.
"That day, I couldn't defend you. I told myself excuse after excuse—that the Founder had entrusted Kiryu to me, that all I could do was stay close and watch—and I just stood by in silence as he became an accomplice to a lie. It took me three years, but at last I've come around to the side that stops it."
Shiina bowed his head once more.
"I'm sorry. I'm truly sorry."
Mio watched him quietly.
Mikoshiba was there. Aya was there. Both of them held their breath, waiting to see what Mio would say in return. Their faces said they expected an emotional reckoning to happen here. Long words of reconciliation, or perhaps tears.
Mio finally opened the canned coffee.
"You don't need to apologize."
Mio said it. Flatly.
"Back then, you gave me production access. That's why I could run my own code on real data without anyone stopping me. Without that, the detection engine wouldn't have been finished. In terms of the data I got, I'm grateful."
"Himuro..."
"And not being able to defend me—that's fine too. Whether you defended me or not carried little weight as a parameter in my life. I had no attachment to the job, and I quit and got myself a different lab. If you're suffering from guilt now, that's your problem. It's not something for me to take on."
Mio took a sip of coffee.
"But—it did help that you reported it to the police. Without that, no one could ever have proven 'they sold it deliberately.' A wall that can't be reached from the outside no matter what. Because you opened it from the inside, it can be settled. Technically, it was the right push. Thank you."
Shiina looked at Mio's face for a while.
Then he laughed, as if the strength had suddenly gone out of his shoulders. It was a laugh close to crying.
"...You haven't changed. Not one thing since you walked out of that conference room."
"There's no reason to change," Mio said, and she meant it.
Beside her, Mikoshiba let out a very small breath. The weight of feeling that Mio had failed to pick up, Mikoshiba was quietly receiving instead. Mio couldn't see it.