Tokyo, washed clean by the rain, had brightened even its darkest corners for a while.
The narrow alley was wedged between two old apartment buildings, barely wide enough for one person to pass through.
In a corner where sunlight never reached, several discarded cardboard boxes were stacked together, soaked dark brown by the rain.
A small lump bulged conspicuously from the middle of the bottom box.
"Rattle... scrape..."
The faint sounds rang out particularly clearly in the deathly silence after the rain. The soggy cardboard covering the lump trembled once, then again.
The next second, an overly pale little hand emerged through a gap in the boxes.
Its fingers were long and slender, its knuckles distinct, and faint bluish veins showed on the back of its hand.
The hand paused in midair, as if checking something, then slowly peeled back the layers of cardboard above it.
Beneath the cardboard was a boy's face.
He looked about thirteen or fourteen. His skin was pale, his hair black, and his wet bangs clung to his forehead.
His eyelashes were long, casting faint shadows beneath his eyelids. He blinked in bewilderment, then braced himself and sat up among the boxes.
The boy settled on the topmost box. Looking down at his thin white patient's gown, he saw that there should have been an identification number over his left breast, but all that remained was a ring of torn threads.
Fragments of memory surfaced from the depths of his mind.
As far back as he could remember, he had lived in a laboratory. Pure white walls, cold fluorescent lights that never went out, and the ever-present smell of disinfectant mixed with some kind of chemical reagent.
At first, there had been ten children like him.
They had no names, only numbers, assigned according to the order in which they had arrived at the laboratory.
He was Number 07, the seventh child to be brought in. No one knew who had brought them there, and no one told them why.
"You were all chosen," the people in white lab coats always said, their voices muffled by their masks. "For a greater purpose."
The weekly biological experiments had begun with allergy tests for various drugs.
Needles pierced their skin, injecting liquids of different colors. Then the researchers recorded the reactions: rashes, vomiting, dizziness, high fevers.
The children huddled behind the observation room's glass, watching symptoms appear on one another and comforting each other with, "It'll be better soon."
In the second year, the experiments became "drug resistance training."
They started taking all kinds of pills and receiving even more injections. Colds, fevers, diarrhea... ordinary illnesses became part of the tests.
A girl called Number 02 never returned to the dormitory after three days of continuous fever.
Third year, fourth year... The children learned not to cry out during experiments.
Crying was useless. It only made the people in white coats record data like "emotional fluctuations affecting physiological indicators."
Until the fifth year.
The experiments became "toxin resistance tests."
They began adding various viral prototypes to the drugs. The children heard the researchers discussing them in private: "influenza variants," "neurotoxin samples," "bloodborne pathogens."
That year, six of the ten beds in the dormitory were left empty.
The four children who remained huddled together in the corner of the room, trying to keep warm.
Number 07 remembered a boy called Number 03. He was always lively and would secretly tell stories about the outside world after lights-out, though he might have made them all up.
"07, I don't think I can hold on." One night, a white-haired girl called Number 09 sobbed against his chest. "03 hasn't come back for two days."
Number 07 had been only eight years old then. He gently patted her back and said, "09, it's okay. We'll make it through. 03 is just tired. He'll come back after he gets some sleep."
But he knew it was a lie.
The rules of their dormitory were simple: if someone was taken away and didn't return within twenty-four hours, they would never come back.
In the corner, the other two children held each other without a word. Oppression filled every corner of the room.
In the sixth year, Number 09 was taken away too.
The empty dormitory was left with only him. The nights grew especially long, and he couldn't help wondering why he was the only one who had survived. During every experiment, he managed to endure right at the brink of physical collapse.
Once, he finally couldn't take it anymore.
It was one night in the seventh year. While the lab staff weren't paying attention, he hid a shard from a broken reagent bottle. After lights-out, he lay on his bed and used the glass to slash his left wrist.
Without expression, he watched the red liquid drip onto the bed as his body grew colder and his consciousness slowly faded.
As he closed his eyes for the last time, all he felt was a wistful sense of relief.
But then he opened his eyes again.
A pure white ceiling, the smell of disinfectant, an IV tube attached to the back of his hand.
His wrist was wrapped in thick bandages. A researcher sat beside the bed, writing something down.
"Awake?" The researcher didn't even look up. "Don't do something like that again. Your life is precious."
From that day on, the laboratory assigned someone to watch over him. A different researcher took a shift each day, sitting by his bed and watching him eat, sleep, and complete his daily tests.
The only "privilege" was that his caretakers occasionally taught him things: mathematical formulas, physical laws, foreign-language vocabulary...
There was also a female researcher who often secretly brought him snacks, most commonly White Rabbit milk candies from China.
In the eighth year, the research shifted to "physical enhancement."
He began learning mixed martial arts, boxing, and jujitsu. In the training room, he fought opponents of all builds and learned how to subdue them with the least effort, strike their vital points, and escape when pinned down.
In the ninth year, combat training advanced to "practical application." Assassination techniques, surveillance and counter-surveillance, using the environment, gathering intelligence.
He was taken outside the laboratory to train in a facility designed to simulate an urban environment.
In the tenth year, genetic modification experiments began.
Purple drugs were injected into his veins, and pain filled his entire body. He endured the first five experiments.
After each experiment, his physical abilities improved noticeably. Opponents who had once required all his strength to handle could now be subdued with ease; complex information that had once taken effort to understand now fell into place at a glance.
Until the sixth experiment.
"Preparing for the sixth gene-fusion procedure," a researcher's voice said beside him.
A needle pierced the side of his neck, and purple liquid flowed into his body. At first, the pain was much like before, but then excruciating agony erupted from deep inside every cell.
His vision began to blur. All he could hear was his own heavy heartbeat and the alarms blaring from the machines.
Just as he thought he was finally going to die, the pain suddenly disappeared.
No, it hadn't disappeared. It had been replaced by something even more terrifying. He felt his entire body dissolving, reforming, collapsing.
The last thing he heard was a researcher shouting in panic. The last thing he saw was flashing red light.
Then he lost consciousness completely.
The boy came back to himself and drew a deep breath. The air after the rain smelled of earth.
He had escaped.
The last thing he remembered was climbing out of the water, icy liquid flooding his nose as he struggled to swim to shore.
Dense woods surrounded him. While hiding in the bushes, he heard the pursuers talking:
"The biological experiment failed, and Director Kaneda escaped."
"Orders came from above to go after him too. What a pain."
"Quit complaining and hurry up and clean this place out. We're short on time. We've got a lot of assignments."
Kaneda Yamano was the man with the gold-rimmed glasses, the director of the laboratory.
Every so often, Number 07 could see him through the observation window. He always wore a spotless white lab coat and always had an expressionless face.
But once, Number 07 saw him take off his glasses to wipe them. Those eyes... were scarlet.
Number 07 shuddered and stood up from the boxes. His patient's gown clung to him, wet and uncomfortable. He checked his body: apart from the scar on his wrist and the needle marks, he seemed unhurt.
As if all those years of experiments had never happened.