Major Case

The sirens blared.

Dark rain clouds loomed overhead.

Kita-Senju Station exit.

The Metropolitan Police Department, the Special Assault Team, and the ambulances formed a dissonant symphony that filled the area with tension. Puddles on the ground reflected flashing red and blue lights. Passersby crowded together to form a wall of people, chattering among themselves. Some would rather be late than miss the spectacle, stopping under their umbrellas to take photos and post them online.

Several reporters stood behind the police cordon in raincoats, facing their cameras and holding microphones as they described what they had just learned.

On camera, heavily armed Special Assault Team members and assisting officers stood guard at their assigned positions. Medical personnel could be seen carrying stretchers, bringing out injured people who were wailing in pain and loading them into ambulances.

"Division Chief Noguchi, we've got information on the perpetrator."

The subway platform was a complete mess as far as the eye could see.

Phones, briefcases, ties, and other belongings were scattered everywhere. Anyone could tell at a glance how much chaos had erupted and how terrified the crowd had been.

When something like this happened in a crowded place, more people were usually injured in the crush than were directly harmed by the perpetrator.

Today was an exception. More people had died at the perpetrator's hands than had been injured in the stampede.

Noguchi Yuji looked away from the perpetrator's body, surrounded by colleagues from the Forensics Division and the Identification Unit, and accepted the file. He skimmed it. The furrow between his brows didn't ease; his whole face seemed to crumple instead.

Sato Gafeng, forty-five, worked in insurance and held the rank of deputy section chief. A kind man, he had a wife and no children. His social circle consisted mostly of coworkers. Everyone who knew him said he was just an ordinary office worker who never lost his temper. He was also in poor health and didn't exercise. Completely ordinary.

"Look into his company and coworkers first. Then find out if he's been in contact with anyone outside his usual circle lately. Also, put his wife under close surveillance."

"Yes, sir!"

Noguchi Yuji took a deep breath and stepped through the open train doors. What met his eyes was a scene like a hellish slaughterhouse, strewn with flesh and severed limbs. The stench of blood hit him full force. Blood had sprayed across the carriage windows, walls, and even the ceiling. A pool of blood had collected on the floor, trickling over the edge of the doorway.

Even as the chief of the First Investigation Division, accustomed to dealing with all kinds of murderers, he was hit by the scene on both a visual and psychological level. He'd heard that several rookie forensic investigators couldn't handle such a "fresh and bloody" sight and had thrown up on the spot.

His gaze passed over the severed limbs that had only just been painstakingly marked. His voice came out hoarse.

"Ordinary, huh."

Shiraishi Wataru considered himself an ordinary person.

He didn't think he was the protagonist of this world. Sure, he was a transmigrator, but he'd ended up in Otherworld Tokyo, and he wasn't even a high school student. Who knew? Maybe he was some minor character who'd get two pages in the manga and three minutes of screen time in the anime.

Maybe he wouldn't even get that.

So he'd always lived cautiously.

He was afraid that if he did something out of line, some ordinary high school student would pop out of nowhere and smite him in the name of the Moon.

Fortunately, the person whose body he'd transmigrated into was a NEET.

He had virtually no social circle and often relied on his older brother even for living expenses.

Unfortunately, the man's memories had nothing of value in them.

His notes app also contained several versions of a suicide note, as if he was convinced he'd either drop dead or kill himself sooner or later.

There wasn't much else to say about him. He could be summed up in one sentence: a hermit who'd lost the courage to face people and interact with them.

His older brother was frustrated with him, but had long since lost the energy to lecture him. Still, their family bond remained. Every month, he paid his younger brother's utility bills and internet fees. He'd even let him have the house their parents had left them, while renting an apartment near his own workplace.

You could call him a great big brother by Tokyo standards. He'd more than lived up to the title.

Shiraishi Wataru had replaced him so quietly because his social connections were so simple.

He'd also started studying his "superpower."

A superpower that seemed to have appeared because of his transmigration.

Parasitism and Symbiosis.

Every week, he could cough up several thumb-sized parasites, depending on how much nutrition he'd taken in, though there was a limit.

Once someone swallowed one, he could choose to parasitize or symbiose with them.

Parasitism meant complete control, but it was hard to control his own body and the parasite host at the same time. After parasitizing someone, he could also use the host to produce new parasites, but strictly speaking, they were transferred from his own body. So having more hosts didn't mean he could produce more parasites.

The other option was symbiosis.

A parasite could share all of his abilities except parasitism with a symbiotic host. It could also give the host a chance to mutate, then pass the resulting ability back to him. It was a mutually beneficial relationship.

But as mentioned earlier, Shiraishi Wataru was cautious by nature. Even when experimenting, he only used small animals such as mice, cats, and crows. He hadn't even tried it on a dog. He never came across stray dogs, and it would've been awkward and expensive to buy one.

For nearly a year since transmigrating, he hadn't dared to try it on a person. Not because he was morally upright, but simply because he was worried about ordinary Tokyo high school students.

The information he'd learned about this world showed that it wasn't the same as his original one. Its technology was even more advanced. He worried that this was some novel or anime universe, and that beneath Tokyo's peaceful surface lurked countless extraordinary people with all kinds of powers and unfathomable methods, as well as student protagonists fresh out of high school with absurd levels of luck.

His cheat ability, which required someone to swallow a bug, couldn't compare to those monsters.

This went on until two months ago.

One of the stray cats he'd symbiosed with was caught by a group of children and tortured.

They burned it, whipped it, and pelted it with stones.

Amid its suffering and the children's laughter, the cat mutated.

[Super Strength] [Steel Body]

The ordinary tabby cat broke free of its tightly bound ropes. Amid the children's screams, it swiped at them one by one, stripping strips of flesh from their bodies and leaving deep, bloody gashes that exposed bone.

Even their clothes couldn't stop its sharp claws. They were as useless as paper against a samurai sword.

The children scattered, crying for their parents. The cat caught up with only one of them—the cruelest of the bunch.

He'd used a branch to poke out one of its eyes. In return, it took one of his eyeballs with its claws. Then, in full view of everyone, it leaped several times to heights far beyond anything normal and disappeared from the witnesses' sight, leaving behind a child sobbing hysterically and screaming in agony. The incident even made the news.

After that, nobody ever saw the cat again. Or perhaps there were simply too many similar cats. Under pressure, the relevant authorities could only make a show of capturing a batch of them and euthanizing them. That alone angered plenty of animal rights activists, who protested outside the shelters every day. Even the shelters' efforts to take in and euthanize stray dogs were disrupted.

For the first time, Shiraishi Wataru received feedback from symbiosis. It didn't simply grant a set amount of extra strength; instead, it adjusted to the user's physical condition.

He gave it a try. He could probably lift an ordinary car, weighing a little over a ton.

For a human, that was undeniably super strength.

The ability also went hand in hand with Steel Body. After all, force went both ways. If you could punch through concrete, your bones would be in pieces too.

Steel Body increased the density of skin, bones, muscles, and the like, boosting physical defense and preventing a situation where you killed a thousand enemies at the cost of injuring yourself just as badly.

With these two abilities, Shiraishi Wataru finally began to act a little more boldly.

He turned his attention to one of the few Company Groups he'd learned about during the past year.

"I'm just an ordinary housewife. I only came to the police station because I couldn't reach my husband this evening, and then I saw the news about the incident. I don't understand why you're asking me all these unrelated questions. Has something happened to my husband? Can I see him? Please, just let me see him, just once. Please—"

The two officers conducting the interview exchanged a glance.

On the other side of the interrogation room's one-way mirror stood Noguchi Yuji, who'd been at the subway that morning. As chief of the Criminal Investigation Division 1, he'd been given control of this exceptionally heinous case. Even the Public Security Department hadn't tried to seize the lead. They'd merely set up a nominal Joint Investigation Department, leaving him in charge.

As the perpetrator's wife, Mrs. Sato had been placed under surveillance immediately. Noguchi had hoped to uncover some useful information, but her behavior was indeed much like that of an ordinary housewife.

She'd spent some time doing housework at home, then cooked and ate lunch. After a nap, she'd gotten up and followed a dance workout on TV. Around four or five, she'd gone grocery shopping. She'd started making dinner at five thirty, and when her husband still hadn't come home, she'd called him. When she couldn't reach him, she'd called his coworkers and company.

They, too, had no idea that Sato Gafeng was the perpetrator of the subway attack that had shocked the country. They'd only told his wife that officers had contacted them that day to gather information about him.

Worried, she'd hurried to the nearest police station to ask what was going on.

The officers watching her had no choice but to report to their division chief. So she'd been brought to the Metropolitan Police Department, leading to the interview now underway.

Noguchi Yuji picked up the freshly printed analysis of Mrs. Sato's background. The pages were still warm.

[Regularly participated in activities held by a certain Company Group. Bank statements showed fixed sums being transferred at regular intervals to the same account. Suspected donations.]

[History of a suicide attempt. Slight mobility impairment in her left leg. Neighbors and employees at stores she frequented confirmed that she had shown signs of the impairment as recently as the day before yesterday. However, since yesterday, June 5, she seemed to have no problems with her left leg. She ran when she came to the police station. Officers monitoring her reported that she moved like an ordinary person, with no sign of a limp.]

[History of miscarriage. Medical records indicated she could no longer have children. She began participating in Company Group activities after this.]

[Went out on the morning of June 5, possibly to attend a Company Group activity. The destination was somewhere near Kita-Ayase. The exact location and group involved had not yet been identified.]

[Analysis point one: Mrs. Sato was unable to have children after a miscarriage and consequently had suicidal thoughts. Her attempt failed, leaving her with a leg injury. She was eventually targeted by a certain Company Group and recruited as a member.]

[Analysis point two: She attended a Company Group activity on June 5. That afternoon, a store employee who knew her noticed that her leg no longer seemed impaired. That evening, Sato Gafeng came home for dinner. Early on June 6, the inexplicable tragedy occurred. There must be a connection.]

[Analysis point three: The Sato couple shared a very deep bond. Recommend not revealing that Sato Gafeng is dead. Use concern for her husband as the reason to find out exactly where she went on June 5, which Company Group's event she attended, where its headquarters are, what strange things happened, what she and her husband discussed that night, and how her leg recovered.]

[Analysis point four: As a precaution, recommend placing an armed response team on standby.]

"Tell her that her husband is currently a major suspect and that she can't see him yet. We need her cooperation in the interview. If her husband is innocent, this is the only way to clear him as quickly as possible."

An instruction came through his earpiece. After listening, the male officer said gently, "Mrs. Sato, your husband is currently suspected of involvement in this case. I'm sure you want him cleared as soon as possible, so you should cooperate with our questions and answer them truthfully. That's the only way you can help him."

Mrs. Sato's face was pale. She lightly tugged at the hem of her clothes, lowered her head, and was silent for a long while before finally replying, "Please, go ahead and ask your questions."