Bio Defense ~A City Built in a World That Has Ended~

Chapter 3-5

Hinata gave the address near her home and asked for a route to return there while avoiding the main streets. If she could just get back to the street with the bus center, she’d manage somehow.

She briefly explained her reason for being there and mentioned that taking the main roads was dangerous because she had inadvertently attracted infected individuals.

“It’d be best if I could find my brother, but in this state… For now, if I can just get back to the bus center, I’ll figure things out from there.”

“I see, you’re looking for your brother… Hinata-chan, you’re amazing. Alright, the bus center, huh? There’s a path that’s not too crowded. It’s a bit tricky to navigate, so I’ll guide you.”

Before Hinata could respond, Katsuya started walking ahead.

“No… I can’t trouble Ookura-san that much. Besides, there might be infected out there.”

Hinata stopped him. Of course, she didn’t want to inconvenience him unnecessarily, but once she knew the route, that would be enough. Based on Katsuya’s earlier behavior, Hinata assumed he’d be easier to deal with alone.

“Don’t worry. I’ve got the movements of the infected down to a T. If you stay behind me, you’ll be fine. Oh, and… we’re not strangers, so just call me Katsuya. It feels too formal otherwise.”

Katsuya smiled sheepishly as he said this, then began walking again without waiting for her reply.

“Haah…”

Hinata sighed, feeling this was becoming troublesome. Calling him “formal” was one thing, but they were barely acquaintances. What did he even know about her? She felt the urge to question him.

Honestly, she wished he’d stop calling her so familiarly and lean a little more toward “stranger.”

For a while, Hinata followed silently behind Katsuya. Despite his claims of knowing the infected’s movements, his actions became increasingly worrisome.

It wasn’t just a matter of combat skill. Even when walking, he made awkward movements as if trying to muffle his footsteps, slowing them down significantly.

Earlier, an infected stood blocking their path. Katsuya stretched his arm in front of Hinata, giving her a “leave it to me” look. She watched in silence as he retrieved a juice bottle from a nearby trash can and threw it in the opposite direction of where they wanted to go.

His plan was likely to create a distraction and move while the infected’s attention was elsewhere. However, the bottle didn’t go far, ricocheting back near them, forcing them to flee in a panic.

Another time, thinking it was just one infected, Katsuya tried to fight using his imitation katana. However, he couldn’t angle the blade properly and ended up hitting with the flat side.

Properly wielding a katana involves pressing the edge against the target and cutting by pulling it. Pushing it can work, but the pull is fundamental. Failing to hit with the blade not only makes it ineffective but also causes the sword to reverberate, sending shockwaves to the wielder’s hands. This applies even to imitation swords.

At the Nishina Dojo, Hinata had trained in these techniques. There were even masters of iai (quick-draw swordsmanship) among the seniors there. But Katsuya, focused solely on looking cool, failed to execute even the basics properly.

Still, when Hinata tried to step in, Katsuya would say, “It’s fine, leave it to me,” with a grin.

It would be fine if he heroically dealt with the situation, but instead, it often ended with Hinata having to lure the infected toward her and fight them herself. It was exhausting.

“Hey, Ooku—ah, cough, cough—Kimi, do you want to try using this?”

Though he kept asking her to call him Katsuya, Hinata settled on calling him “Kimi” (you), feeling it was a good compromise. Begrudgingly, she offered him Onimaru, her trusted weapon.

If he couldn’t handle the katana at all, he’d be useless in an unexpected encounter. Hinata trusted Onimaru, which fit perfectly in her hands, and hoped it would improve his performance.

Katsuya’s face lit up momentarily but quickly turned conflicted as he compared his imitation katana to Onimaru. Reluctantly, Hinata explained:

“Since I’ve trained in swordsmanship, I’m more accustomed to handling a blade. Onimaru… I mean, the iron pipe doesn’t require precision, so…”

Why did she have to explain herself so much? She felt a twinge of sadness at the thought.

Misinterpreting her, Katsuya responded with, “Yeah, a katana’s better than a pipe. I get it.”

Hinata couldn’t help but think, “…I just want my Onimaru back.”

Perhaps distracted by their exchange, they didn’t notice an infected lurking behind a vending machine. It reached for Hinata, and she spotted Katsuya scrambling to raise Onimaru. But she didn’t have time to wait.

Gripping the scabbard of the imitation katana, she focused her aim and swiftly drew the blade.

The unsheathed sword accelerated with a sharp whoosh, slicing through the air. She targeted the infected’s neck, which had a bite mark—a likely cause of the infection. The precise strike landed cleanly.

It didn’t cut, as it was a blunt imitation sword. But if it had been sharp, it might have decapitated the infected. That’s how precise and powerful her iai strike was.

“Guh…”

The air hissed out from the infected’s gaping mouth, sounding like a final death rattle.

The infected collapsed unnaturally, its neck visibly fractured.

“Amazing…”

Katsuya couldn’t help but gasp. Though he had dismissed the imitation katana as ineffective, Hinata wielded it with enough force to shatter bones.

Katsuya had to acknowledge the vast gap in skill between them. He admired her strength, grace, and the kindness she showed by even offering prayers for the infected she defeated.

If they continued walking, the bus center would come into view in about ten minutes. Once they arrived, Hinata would return to her original destination. That would be the end of their time together. A farewell. It was truly regrettable… Katsuya didn’t want to part ways.

Hinata had the strength to take down an infected with a single blow when wielding a sword, yet she never lost her gentle heart. Even now, she clasped her hands together in prayer for the infected she had just defeated. She had done this every time unless the situation was truly dire.

Even someone like Katsuya, with all his flaws, was treated kindly by her. The thought of someone else monopolizing that kindness filled him with frustration. At first, he had simply felt reluctant to part with her and had forced himself to tag along. But deep down, he knew—he was drawn to her.

Just a little farther. If they turned the corner ahead, the bus center would come into view.

But with every step closer, an urgency, mixed with dark emotions, began to stir within Katsuya. Thoughts raced through his mind, most of them far from virtuous.

Why should he simply let her go? Even the brother she had been searching for might already have fallen to the infected, wandering aimlessly as one of them by now.

“Tch, if that’s the case, then he might as well show up around here,” he muttered bitterly.

As the fulfillment he had felt from being with Hinata began to fade, the malice that had always been buried within him started to whisper again.

“What’s wrong? Oku… are you hurt somewhere?”

Hinata’s gentle voice broke the silence. She had noticed that Katsuya had stopped walking and turned to check on him. Her concern was genuine, but her words no longer reached him.

“No, sorry. I was just lost in thought,”

(…She still calls me Okura. No matter how many times I’ve asked, she won’t use my name. If only we had more time together… if only I had more time, she’d see the good in me.)

Katsuya walked on, his head bowed, as his thoughts accelerated.

(Look at the world around us. Monsters everywhere. The police and government aren’t functioning. Whatever you want, you take it—by any means necessary. That’s how I’ve always done things.)

And so, the old Katsuya stirred awake once more.

Something about Katsuya was strange. Hinata couldn’t help but notice. He had gone quiet all of a sudden. When she asked if he was feeling unwell, his response was brief, and he quickly started walking again. But his behavior was clearly unusual.

Concerned, Hinata kept glancing at him, but Katsuya continued ahead without looking back. As she followed him, they eventually emerged onto a wide street. A familiar shop caught her eye—one she had visited before with friends to buy small items.

If that shop was here, then… Hinata turned to the left. Sure enough, the bus center they had been searching for was finally there.

“Oh, thank goodness! I’m so sorry for making you guide me all the way here. You’ve been such a big help!”

Relieved, Hinata broke into a bright smile and bowed her head to Katsuya. For a moment, Katsuya’s expression turned cold.

By the time Hinata raised her head, his coldness was gone, replaced by his usual smile. But something about him felt… off. She couldn’t quite place it.

“From here, can you make it back on your own?” Katsuya asked before Hinata could dwell on the unease.

“Yeah, I’ll be fine from here. I’ve been here before with friends and family. Really, thank you. And also…”

Hinata trailed off, hesitating for a moment. She looked down, gathering her thoughts, before finally raising her head again, her cheeks slightly flushed.

“Um… How should I say this? You were a lot kinder than I expected. Sure, you’ve got a few quirks, but… you’re not as bad of a person as I thought. When things go back to normal… let’s meet again at school, Katsuya-kun.”

With a warm smile, Hinata handed the imitation sword she had been carrying back to Katsuya and took the iron pipe from him instead. Then, with a small wave, she turned and ran off.

A few moments ago, when Katsuya had been somewhat influenced by Hinata, he might have been overjoyed by her words, or perhaps turned bright red and frozen in place.

But the Katsuya standing there now was the old Katsuya. “Kinder than expected”? “Not a bad person”? Those naive words of hers…

Hinata-chan, you don’t understand. Thoughts like that will get you killed in this world. I’m the one who has to protect you.

A dark smile spread across his face as he watched Hinata disappear into the distance. Then, with an exaggerated expression, he called out loudly.

“Hinata-chan!”

TIPS: Imitation Sword (模造刀)

The imitation sword used by Katsuya in the story is sturdy enough for iai practice. It’s heavy and, when wielded correctly, can serve as an effective weapon. However, Katsuya’s lack of skill means he can’t fully utilize its potential.