9 The Sensory Deprivation Experiment

Not far away, the white-haired teacher watched his adorable students playing with a smile. Only when they had finished did he approach and, with practiced ease, rest his hand on Itadori’s shoulder.

"Are your goodbyes done?" Gojo asked.

Yuji Itadori felt his shoulder sink and looked back. "Teacher, you’re here!"

"The principal told me that you and Kugisaki would be going on a mission with me today."

Gojo nodded. "You’ve both been training with Yuuki recently and making rapid progress; it’s time for some field experience."

"Yuuki, don't feel lonely, either. Teacher has arranged a very reliable guardian for you."

Yuuki Ieiri nodded. "By the way, teacher, Tamayo will be staying at the Gojo estate for the time being."

"That’s fine."

Since yesterday, Lady Tamayo had borrowed many medical books and several cursed spirits from Gojo. She had then locked herself in a specially prepared room and had not emerged since. This left Yuuki Ieiri, who had been hoping to watch a live dissection of a cursed spirit, feeling rather disappointed...

*Ahem.*

He wasn't a pervert; he was just curious.

Seeing that their conversation had reached a lull, Kiyotaka Ijichi summoned his courage and stepped forward.

"...Gojo-sensei, Student Ieiri should be heading to the mission site now."

Ijichi had been a corporate drone for many years, but his eloquence and courage had never truly been honed. Deep down, Ijichi was weeping.

[It’s me...]
[I’ve resonated with Ijichi.]
[Treating work as just work, doing neither well nor poorly, lacking ambition, clocking in and out exactly on time, wanting to resign at every moment, and only earning that meager pittance of "coward's pay"...]
[Enough! I came to watch a livestream, not to look in a mirror! Waaah!]

Amidst the constantly scrolling comments, the students went their separate ways. The camera followed the black car carrying Yuuki Ieiri as it gradually moved away from the quiet, ancient residence.

Ijichi glanced at the rearview mirror. "Ieiri-kun, this is your first mission. Gojo-sensei has arranged for a second-year student to accompany you."

"His name is Toge Inumaki, a Cursed Speech user. We’ll go pick him up first."

"Also, here is the information for this mission. You can take a look at it, Ieiri-kun."

Ijichi, being very responsible, briefly explained the mission content: "This request came in from the police."

Multiple fatalities had occurred in an old apartment building. Each person died in a different way, and the states of their bodies were exceptionally gruesome. Five people had died within a single week.

[Five in a week?]
[That’s a high number.]
[I’m very curious, can Japan’s population really handle this kind of chaos?]
[It reminds me of the quaint, simple town of Beika.]
[The Eastern Gotham City.]

Yuuki Ieiri nodded while listening, spreading out the documents.

The first page stated that the mission was classified as Grade 2, requiring the exorcism of a Grade 2 cursed spirit. Flipping to the next page, he saw photos of the victims.

An unemployed youth had fallen to his death while leaning against an old, dilapidated window to smoke; an office worker had been pierced through the throat and suffocated by the tip of an open umbrella at the apartment entrance; a divorced man had been electrocuted while bathing; an elderly person had suffered a heart attack; and the last was an employee of a host club who had fainted on his way home, hitting his head on a roadside rock and dying from a puncture through his temple.

The victims were all tenants of the same apartment complex.

Judging by the investigation results, the five deaths were all non-human-caused, all accidents. But for so many "accidents" to occur in just a week, they could no longer be considered mere accidents.

The police had found nothing and reported it to the Jujutsu Headquarters. The latter sent personnel to investigate and confirmed that a cursed spirit was indeed at work.

There was one survivor remaining in the apartment. However, he had been so terrified that he had fled to a nearby shrine, chanting scriptures day and night.

"The initial assessment is that there is something wrong with the apartment itself, which is why it killed the tenants," Ijichi said. "So, we will go to the apartment to investigate first, then head to the shrine later."

Not far ahead, a sudden "rustle" came from the dense green woods by the roadside. A figure leapt out!

Kiyotaka Ijichi, who was driving, was so startled he nearly slammed on the gas. Fortunately, at the last second, he recognized the figure—it was the second-year student he had mentioned earlier: Toge Inumaki.

The boy with short white hair had the lower half of his face covered by his raised collar, and he walked over with a light step.

Ijichi rolled down the window, looking ghastly. "Inumaki-kun, it’s you..."

Inumaki raised a hand and greeted, "Kelp."

[Inumaki-speak.]
[Kelp usually means 'Hello.']
[A cute baby!]

"Hello, Inumaki-kun," the assistant supervisor said weakly. "I recall you were supposed to be on a mission in a village a few kilometers away..."

Inumaki: "Pollack roe, mustard leaf."

Ijichi tried to decipher these words. He had learned some of the "Inumaki code" from Maki-san last time: "Danger? It’s over?"

Did that mean the mission was finished?

[Pollack roe means 'danger,' mustard leaf is 'safe.']

Inumaki nodded to confirm, then opened the car door and sat in the back. He already knew there was someone inside—a first-year freshman. With the demeanor of a senior, he greeted him: "Kelp, kelp."

[Hello, hello.]
[So cute, I’m fainting.]

Yuuki Ieiri also found him adorable and replied, "Kelp, kelp."

"Inumaki-senpai, nice to meet you. I am Yuuki Ieiri."

"!" Upon hearing the familiar term, Inumaki’s eyes lit up.

What an interesting junior!

[They hit it off.]
[Wait? I thought he had a cold, aloof personality.]
[No, no. Because of Cursed Speech, Inumaki can't speak freely, but he’s actually very lively.]
[Inumaki basically uses rice ball fillings to speak, but he’s great at stirring things up.]

The two quickly became familiar and exchanged contact information.

Yuuki Ieiri discovered that Inumaki’s typing speed was incredibly fast! It was even faster than Yuuki’s normal speaking speed. According to Inumaki, it was the result of over a decade of practice; he could even type without looking.

And so, one speaking and one typing, they chatted the entire way.

On the day Yuuki Ieiri triggered the cursed spirit riot, Inumaki had not been at the technical college. Or rather, none of the upperclassmen were. Now that it was the beginning of summer, cursed spirits were popping up like bamboo shoots after a spring rain, and all the students capable of exorcism were out on missions. They were working back-to-back shifts and basically had no time to return to the school.

And if nothing went wrong, this high-intensity work would continue for two or three months. So, when he was out on a mission and heard the school had been destroyed, he was actually a bit happy.

Inumaki: [Thanks to you, the school can be rebuilt. I’m going to suggest to the principal that we clear a plot of land in the back mountain to grow vegetables and raise pigs or something.]

Yuuki Ieiri: "...Raise pigs?"

Inumaki: [You don't know yet? The cafeteria at the school is super gross. I ate there for two days, then bought a month’s worth of cup noodles.]

Inumaki: [I only went back to the cafeteria when I felt sick from the noodles.]

Yuuki was surprised: "Is it that bad?"

It was unexpected.

Inumaki was also helpless, as there were too few students at the school: [There are fewer than ten students from first to fourth year combined, and most are out on missions, so the cafeteria isn't very functional and they won't change it.]

Inumaki: [But for the first-year students who mainly spend time on campus, it’s a form of torture.]

Inumaki: [There are only two reasons to eat at the cafeteria: one to save money, and two to stay alive.]

Inumaki: [So I suggested to the principal that we might as well raise some fresh ingredients so we can get them when we're hungry—or rather, cook for ourselves.]

The white-haired boy’s fingers were typing so fast they left a blur—he clearly held a deep grudge, Yuuki thought.

[Reminds me of my school... Stir-fried tomato with egg is normal, right? Who knew it would be cherry tomatoes stir-fried with boiled eggs?!]
[That’s evil!!]
[I’ve even seen stir-fried watermelon with green onions.]
[That is heresy, absolute heresy! Burn it! Aaaah!]

"Buzz—"

A vibration suddenly sounded. The two confirmed it was Yuuki Ieiri’s phone. Inumaki immediately paused the conversation, signaling for him to check it.

Yuuki Ieiri took out his phone and saw the sender: Lady Tamayo. His summoning technique couldn't communicate telepathically with his shikigami like Megumi’s could, so they had to communicate like humans. And since the sounds made by cursed spirits couldn't be recorded by electronic devices, they couldn't call, so Yuuki had thought of a method—

Texting.

He didn't expect the text to come so soon. Logically, Lady Tamayo should still be in the dissection room. Had something gone wrong? Or had she made a discovery?

Thinking this, Yuuki opened the message.

The message from Tamayo wasn't long, but the content had nothing to do with the dissection: "Master Yuuki, could you let me 'return'? I want to try an experiment."

'Return' likely meant returning to the place where the shikigami waited when they weren't summoned.

Yuuki Ieiri: "Okay."

Tamayo: "I want to try to see if I can bring things existing in the real world back with me when I return, such as paper, cursed spirits, or cursed tools."

The two messages came one after another, less than half a second apart.

[Pocket dimension?]
[I remember Megumi’s Divine Dogs could bite cursed tools and hide them in a different space.]
[But Megumi can summon his shikigami at any time and communicate with them telepathically; Yuuki is a bit different.]
[Still, honestly, Lady Tamayo’s proposal is very forward-thinking.]
[Yuuki agreed so readily.]

He didn't even make Tamayo wait for three seconds.

Tamayo was silent for a moment before a message came through: "Thank you for your trust."

Yuuki: "It’s a small favor."

"By the way, Lady Tamayo, may I ask, what is that space like?"

Tamayo replied, and the phone vibrated slightly: "There is no light, sound, or time. It is a dark, boundless space drifting outside the world."

[I have a sense of déjà vu, but I can't place it.]
[Is it Donald’s 'dark room' experiment? If you stay there too long, you’ll definitely go insane...]
[What is that?]
[It’s where they make you wear a blindfold, gloves, and earplugs—effectively blocking vision, hearing, and touch—and then put you in an isolation chamber.]
[Sensory deprivation.]
[The results showed that people in this environment generally have abnormally high brain activity and even start to hallucinate.]
[They constantly try to imagine scenes, and these hallucinations are beyond their control; they are almost purely instinctual.]
[This is exactly what Muzan is going through now, isn't it...]
[What is he thinking about?]

Yuuki Ieiri controlled the flow of his cursed energy; it felt as if a thread inside him had snapped. It felt similar to when Muzan disappeared.

It should have been a success, right?

Well, it would need a two-hour cooldown now.

"Screech—"

The sound of tires rubbing against the pavement. Without realizing it, the black car had arrived at its destination: an old apartment building in Kyoto.

Ijichi turned off the engine and said: "Inumaki-kun, Ieiri-kun, we have arrived. This is the crime scene."

The area was already cordoned off with yellow police tape. As soon as they got out of the car, a police officer in plain clothes walked up, recognizing the assistant supervisor in the black suit: "Mr. Ijichi?"

"Officer Sudo, we meet again."

It was summer, the peak season for cursed spirits, and the students from the technical college were basically always on missions, so it was inevitable they would greet the officers. Both sides had an impression of each other.

Kunihiko Sudo approached and immediately saw the new face behind Ijichi—a blonde, blue-eyed boy wearing a sleeveless top, cargo pants, and combat boots, looking handsome and sharp. Attached to the boy’s belt were several palm-sized pouches, bulging as if they contained something.

Officer Sudo told himself not to be curious. He pulled back the tape and led them into the ominous, unvisited apartment.

Ijichi stayed outside, taking the opportunity to set up a veil.

"This apartment is quite old, but the rent was cheap, and people have always rented rooms here, but this year, strange things started happening," Officer Sudo said.

Inumaki and Yuuki followed behind him.

Stepping into the area marked by the yellow tape, a strange smell immediately filled their nostrils...

The two boys looked at each other—it was the stench of rot.

Officer Sudo, walking in front, didn't seem to notice and continued: "These six tenants, starting a month ago, began to have their wishes fulfilled."

[Wishes fulfilled?]

Officer Sudo repeated a line written in the investigation report: "As long as it was something they said inside the apartment, it would become reality."

"They all turned into manifestations of cursed speech."