The proof had been broken open, from the inside.
With his apology brushed aside by Mio, Shiina let his shoulders relax for a moment. Then he straightened himself and broached the other matter that had brought him here. What came after the report. Still perched on the edge of the reception sofa, he told Mio and Mikoshiba how it had all played out, to the very end. Aya, too, listened in silence by the wall.
"What I gave the police were the contracts and the records of the money transfers. And the access logs that explicitly approved providing Kotoba's user data and the detection code Himuro left behind to third parties. Everything I could take out, all of it. The seal of approval on those was stamped on every one of them under a single name."
Sota Kiryu.
Providing data to third parties without the users' consent ran head-on into the Personal Information Protection Act. And since that data had in fact been used by scam rings for "sorting marks," aiding and abetting fraud was also in question. The investigation reached into Kotoba itself.
"I hear the final shot that broke the wall was your graph, Himuro," Shiina said, looking at Mio. "You'd drawn every last line of data and money flowing from Kotoba to the scam rings. That's why my materials could shoot through to 'intent.' A wall that could never be reached from outside—you had whittled it down from the outside, as far as it could go."
Mio said nothing. Half of the canned coffee in her hand still remained.
"With President Kiryu," Shiina said, lowering his voice, "the night before he was to undergo voluntary questioning, I faced him just once. As the Founder's right-hand man, one last time."
Mio hadn't been present. But through Shiina's voice, the chilled air of Kotoba's president's office alone came through.
"'All you've done is devour what the Founder left behind.' Without raising my voice, I left him with just that. The one name Mr. Kiryu can never defy—the Founder. His father. The name of the man whose back he had never once managed to catch up to."
Shiina lowered his eyes.
"The Founder built that company saying he would 'connect people with words.' He thought of the people who trusted their words to him as a treasure. Mr. Kiryu turned that treasure into a list and sold it to the side that deceives. That isn't management. He simply converted the trust the Founder spent thirty years building up into cash, and spent it all."
"And so," Mio said, speaking for the first time, "what did he say?"
Shiina smiled bitterly.
"'Data is an asset, isn't it? What's wrong with putting it to work? What's wrong with selling user data? I just did a new kind of business. You people are old-fashioned and can't understand that.' He spat that out and turned his back on me. To the very end, that was how it was."
Mio drank down the last mouthful at the bottom of the canned coffee.
The people turned into marks had in fact been robbed of their money, had pieces of their lives cut away. Code she had written to protect had turned into a tool for hunting. And the man who had pulled that trigger by selling the data did not understand, to the very last, a single letter of what he had destroyed.
"...As expected."
Mio set the empty can on the desk.
"How boring. That man was never someone who updates his prior, from the start. Ever since he cut me off at the previous company as a little girl with nothing but a high school diploma, he hasn't once raised the precision of his observations. Sell the data, and there are people on the other end. Those people get deceived. That line of cause and effect was never drawn inside him in the first place. Someone with no line doesn't come to see one. The input needed for updating doesn't even get through."
It wasn't a triumphant voice. It was just a voice like someone flatly reading out the answer to a problem they had solved.
Shiina looked at her profile for a while. Then he slowly rose from the sofa.
"I couldn't stop it. For all that I was the Founder's right-hand man, all I could do was watch his reckless course from close by. It's because you were there, Himuro, that I could finally bring it to an end. I thank you. I've handed over what I needed to hand over. From here on, it's my turn."
From here on, questioning and a fitting share of blame awaited him, too. As one of the accomplices, he would set things right himself as well—Shiina said it quietly, with the face of someone who had accepted that.
"Take care, Himuro. I'm glad I got to see you facing the world properly, in your own way."
Mio didn't stand. She only nodded.
"You saw the homework you'd been carrying through to the end too, didn't you. As observational data for me, it wasn't bad."
At those words, Shiina laughed in a way close to crying. He bowed his head deeply just once more and left the reception area. His steps were those of someone who had no intention of ever appearing before Mio again.
The rot had been drained, all of it. Kotoba was finished, the second-generation president along with it. The technical homework Mio had seen crushed at her previous job, and the guilt Shiina had carried for three years, had each been seen through to the end, by their own hands.
Mio didn't indulge in sentiment. A line had been stepped over, so she had put it back. That was all there was to it.
Only—Makoto had been protected. The flag Mikoshiba had raised, a social network without scams, still stood there, not painted over by the side of lies.
That was enough.
"It's over," Mikoshiba said beside her. A long breath was mixed into his voice.
"Yes," Mio nodded. "Domestically, at least."
Mikoshiba looked at her.
"Domestically?"
Mio's eyes were already looking at the next graph. The network of withdrawal runners, the money windows, Kotoba's collusion—they had been cut off here. But on the map Mio had drawn, there still remained a number of lines she hadn't been able to trace all the way, still extending beyond the border.
"The main stronghold is still across the sea."
Mio said it quietly. The rot had been drained. But that was only a story about a tiny part of a much larger body.