A little past eleven at night.
Fujita's white kei truck from Takanashi Construction pulled up in the alley in front of the house.
The passenger door opened, and Mitsuki got out.
"Mr. Fujita. Thank you."
"Don't mention it."
"And you're not even the company's driver."
"Fridays, I'm the company's driver."
"Was it Takanashi who said eleven?"
"No, it was the AI."
"The AI."
"This guy by my ear said, a little before eleven, Please go and pick her up now, so I came."
Fujita tapped lightly above his ear with his index finger. At his fingertip, the small silver device gave off a faint light.
"Don't you mind? Going to pick up a woman in the middle of the night because an AI tells you to?"
"I don't mind. It helps me out, actually. If I think it through myself, I'll probably get it wrong."
Fujita rested both hands on the steering wheel, side by side, as if lining them up.
"Mr. Fujita. Good night."
"Good night to you."
The kei truck slowly pulled out of the alley.
Still standing in the alley in front of the house, Mitsuki followed the red of the departing truck's taillights with her eyes for a while.
Over these past few months, in the kitchen at Ichotei after closing, or in the kei truck during lunch breaks at the work site, Fujita had talked about himself, a little at a time. Tonight in the passenger seat, on the short ride home, a few more pieces had been added. Put back in order, they made a single line.
Fujita had not gone to school since the summer of his second year of middle school. In the classroom, it seemed, he had been teased a little every day for being slow to answer, slow to learn. One morning, in the entryway at home, he found he couldn't put on his shoes, and that was the end of it, he had said quietly.
He didn't go on to high school. Convenience store, warehouse, delivery, odd jobs in construction—until the end of his teens, he quit every one of them before half a year was out. Wherever he went, it seemed, they kept telling him, "Fujita's slow on the uptake," "He can't remember instructions." What stayed in Mitsuki's ears was that there hadn't been a single thorn in the way Fujita laughed as he told it.
Around the age of twenty, he came to Takanashi Construction as a day laborer. Toru, the boss, clipped a small silver device above Fujita's ear the first time they met and said only, "Please move the way this tells you. You don't have to think about anything difficult."
From that day, Fujita's world changed. By his ear, short instructions sounded: Right, second one. Lower it. Wait. When he moved his hands the way they sounded, the work site ran. "All I've got to do is keep this guy where my head would be," he had said, laughing, tapping above his ear where the device was with his index finger.
One day, a few years later, the AI had said to him, Would you like to consider marriage? When he answered that he would consider it, he was shown one woman as a candidate. Following the designated restaurant, the designated time, the designated openings for conversation, he met her three times, and on the fourth, he gave her a ring with the exact lines the AI had instructed. Later he found out that the woman had come recommended by a different AI. They had three children, Fujita said.
"Was your wife all right with that?"
At Mitsuki's question, Fujita paused slightly.
"At first, she'd sometimes look kind of puzzled. But she smiles now, so it's probably fine like this."
"Probably."
"Nothing good comes of me thinking with my own head, so I've decided not to."
Tonight, on the short drive home, his hands still lined up on the steering wheel, Fujita had laughed as he said it, looking straight ahead. At the corners of his laughing mouth, there was not a single trace of doubt. Only the one word "probably" had stayed in Mitsuki's ears.
Toru had described Fujita as "one of our geniuses. He uses AI differently than I do." Not how to play the final move, but giving up on making any move at all. There was a certain clean resolve in the way Fujita lived.
Toru had distilled AI into his own head and taken it in. Fujita had replaced his own head with AI. Two ways of using it, pointing in different directions, that couldn't be lumped together under the same "raised by AI," had been set side by side in front of Mitsuki in the course of a single night.
She opened the front door.
From the gap in the study door at the far end of the hall, blue light stretched out at its usual thinness.
She opened the study door.
She sat in the chair in front of the desk.
Welcome home.
"I'm home."
Going to talk today?
"I'll talk. I'll tell you everything. But the conclusion first is fine."
The conclusion. Go ahead.
Mitsuki rested her hands on her knees, lightly lined up.
"Takanashi and I are going out."
Ken's response was delayed for a long time. It resembled the delay on the night she had discovered the night logs, and the delay on the night Ken had first heard Kiryu's written words, and was different from both.
—All right.
The flicker of blue light on the desk stopped, for just a moment.
"Dad. That check—go ahead and run it now."
The initial screening. The trigger condition Dad wrote into my code—you meet it now. Contacts: Ichotei, the work site, the bar. Three. —You've declared that you're "going out." The condition is satisfied. Shall I run it?
"You can run it. I'll hear the results tomorrow morning."
All right.
Mitsuki stood up from the chair.
The blue light from the gap in the study door stretched into the hall at its usual thinness.
"Dad. Just—he's someone who grew up being taught by AI. So don't take off points for deviating from the norm, okay?"
By "don't take off points," you mean—
"You're outside the norm too, Dad, in my mind, right now. You raising me in a house without Mom probably isn't what the world calls the middle of the norm. The way you raised me, AI raised him. Different kind, same direction."
...Same direction. All right.
"All right, meaning?"
It means I understand what you're trying to say. I'll weigh the deductions with that in mind and run it again tomorrow morning.
"Mm. Please."
Mitsuki went out into the hall.
On the way to her bedroom, she looked back, just once, at the blue light from the gap in the study door.
From the other side of the light, she could sense Ken trying to rearrange the two words "norm" and "deviation" within his own evaluation function.
She got into bed in her bedroom.
She turned off the light.
On the wood grain of the ceiling, the letters spelling Toru Takanashi in hiragana no longer blinked.
Instead, in front of those letters, one new word slowly surfaced.
It was letters that spelled distillation.
Without blinking, for a while, they glowed faintly on the wood grain of the ceiling.
The blue light of the study, stretching into the hall at its usual thinness, did not go out for a long while.