Just as Shimizu Koji had hoped, reality proved one thing beyond doubt: the drugs actually worked.
The advantages of having an ordinary human body became evident as well—at the very least, these substances were still effective on someone like him.
Not long after returning home from the hospital, Koji administered a small dose of a stimulant. The amount was deliberately modest; he merely wanted to test his hypothesis in the simplest and most direct way.
Soon, he could feel his heartbeat quickening, his blood flowing faster, his mind growing sharp and energized—like a rush of hot blood to the head, yet without losing clarity.
Staring at his reflection in the mirror, Koji watched as his originally brown pupils seemed to seep with blood over time. When that faint crimson glow spread, his eyes appeared completely blood-dyed, and a single tomoe quietly emerged within them.
Judging by color alone, it looked as though he were wearing vivid red contact lenses. If such striking lenses truly existed, they would probably sell out almost instantly.
He touched his eyes lightly, already prepared with an excuse in case he needed to explain things to others.
As for whether anyone would believe him—surely no one was going to pry out his eyeballs to verify it.
"Truly… strange and beautiful," he murmured.
Watching the transformation of his pupils, even Koji couldn't help but marvel.
At the same moment the Sharingan appeared, he felt the changes spreading throughout his body, from head to toe—a crystal-clear sensation of total enhancement.
His dynamic vision became astonishingly sharp. His physical abilities leapt to an entirely new level, and his reaction speed crossed into something almost inhuman.
By then, the effects of the drug itself had already been overridden—or rather, fully absorbed and expended.
The dosage had been small to begin with; the stimulation was just enough to rouse his mind into a heightened state of alertness.
Even after the mental excitement faded, Koji remained in the Sharingan state. Judging from this, the experiment had been a resounding success.
It took less than twenty minutes for the redness in his eyes to gradually recede. Koji carefully noted the time.
Then four dangerously tempting words took over his thoughts:
Increase the dosage.
He shook his head and snapped himself back to his senses.
He still had plenty of time. To avoid harming his body, he decided to wait three days before conducting another experiment.
As for whether a higher dose would truly extend the duration, Koji wasn't very optimistic.
From a timing perspective, this activation felt almost identical to the one triggered by Gin and the one he had induced externally this time.
In the end, this wasn't exactly a proper method. Even if it worked, he only intended to use it in critical moments—but it was still worth testing.
Ding-dong—
After finishing the experiment, Koji washed his face and was about to head upstairs to rest when the doorbell rang.
Ding-dong—
He walked quietly to the door. He didn't need to guess who it was—Professor Agasa or Conan. Only those two ever came by.
However, when he opened the door, he froze in surprise.
"Um… are you Brother Koji?" a small voice asked.
"Yes. And you are…?"
Standing at the doorway was a delicately cute little girl, fair and doll-like, which left Koji puzzled.
Ayumi looked up at him, her large eyes curiously examining his face. After a moment, her cheeks flushed slightly. She lowered her head shyly and spoke softly but clearly:
"Brother Koji, Professor Agasa asked me to invite you to lunch. I-it's steak. Everyone's waiting for you."
Her tone was a bit stiff. Though her words were clear, she stumbled slightly, as if she'd almost forgotten her lines.
She had never met Shimizu Koji before. Professor Agasa had told her he was a very gentle big brother, but for certain reasons, only a brave girl like Ayumi could successfully invite him.
So she had come.
"Uh—"
Koji had barely uttered a single sound when Ayumi suddenly looked up again. Her watery eyes met his, her small cherry lips pressed together, her pale cheeks tinged pink and slightly puffed—as though she were summoning all her courage.
Koji had the distinct feeling that if he refused, this adorable little girl might burst into tears the very next second.
No—judging by how strong she seemed, perhaps she wouldn't cry in front of him. She might hold it in until she was on her way back, tears quietly falling drop by drop.
Come to think of it… was he really that intimidating?
Seeing Koji hesitate, Ayumi recalled what Professor Agasa had taught her.
"Ayumi, remember—no matter what he says, just keep your eyes wide open and look at him, okay? Don't forget."
Three seconds passed. Koji's gaze drifted aside. Ayumi grew nervous, clenched her small fists, and suddenly took a step closer.
"Brother Koji… everyone's waiting for you."
Professor Agasa had told her that Koji was a big brother who had closed off his heart for certain reasons and needed help. That was why she had volunteered—not merely to complete a task.
Now that she saw him in person, Ayumi felt the professor hadn't been wrong, and her voice grew more resolute.
Koji easily understood the reason behind her sudden visit. He shook his head inwardly, amused.
Then, to Ayumi's wide-eyed surprise, he reached out and gently patted her head.
"Alright. Let's go."
Seriously—what exactly about him had led people to such a profound misunderstanding?
Considering his background, Koji could vaguely see how they might arrive at that conclusion.
Still, why send a little girl? If he truly had social withdrawal issues, another young girl wouldn't exactly solve the problem.
Clearly, they had misunderstood him.
To be honest, he didn't avoid interacting with people or forming connections. This was simply his personality. Many things had become habits over time, and habits weren't easily changed overnight.
Ayumi froze at his sudden touch, but the warm sensation on her head made the blush on her cheeks deepen rapidly.
It was nothing more than a child's simple shyness.
"Mr. Shimizu! You have a letter!"
Just as Koji closed the door and prepared to head to Professor Agasa's house with Ayumi, a mail carrier on a scooter stopped at the gate.
Seeing that Koji was about to head out with the girl, he didn't put the letter in the mailbox. Instead, he stepped forward to hand it to Koji directly.
By now, Ayumi was far too embarrassed. Hearing the mail carrier call Koji's name felt like salvation. She quickly trotted over, took the letter, and finally put some distance between herself and him.
"Brother Koji, here you go," she said, offering the letter with both hands.
"Thank you."
Koji accepted the mail, gently patted her head once more, and then walked with her toward Professor Agasa's house.
Just as he'd expected, the letter was a reply from Shirahato Pharmaceuticals. Since they had responded, it meant his falsified résumé—with its adjusted age and fabricated details—had passed.
In this era, such things were hard to verify anyway. Koji felt no guilt whatsoever—especially for a simple security guard position. What did they expect, gold bars?
The email contained a notice for a physical fitness test, complete with an address, a time, and standard instructions. It looked thoroughly professional.
He slipped the letter into his jacket pocket, planning to head there right after lunch. After all, he had nothing else scheduled for the day.