It's been four days since Osamu and the group of girls arrived at Rias Gremory's mansion, a place that became their temporary refuge in the midst of the chaos. This house, away from the noise of the city, was practically a paradise within the hell the world had become. With self-sufficient energy, potable water supply, and a well-stocked pantry—enough for at least a couple of months if managed carefully—it seemed like the ideal place to weather the storm.
However, even paradises have their cracks.
During these days, Osamu and the girls didn't just rest; they also reflected on their immediate future. They knew that this peace was only temporary. Sooner or later, the supplies would run out, and they'd have to risk going outside to gather more. But they weren't alone. In addition to them, there were eight guards posted by Rias herself, responsible for the security of the place.
Rias had suggested to Osamu that, when the time came, she could send her guards to gather what was needed. It was a logical option... if they still lived in the old world. But that was no longer the case. The apocalypse had changed the rules. Laws, morals, manners... all of that had vanished along with civilization. Now, the law of the strongest reigned.
Osamu, cautious from day one, had been observing the guards. Something about their behavior told him they weren't as loyal as they appeared. And his suspicions were soon confirmed.
The guards no longer seemed interested in following orders. Their gaze was different, their movements more relaxed, but with that dangerous hint of someone who feels entitled to everything. It was only a matter of time before they took complete control of the house. And according to rumors that were starting to circulate, their first step would be to kick Osamu out.
Just him.
Why not the girls too? The answer was as obvious as it was repulsive. They didn't see them as companions in the refuge, but as... rewards. In this new world where the darkness of the human soul bloomed without restrictions, the guards were no exception. Those men who had initially seemed professional and polite had begun to show their true nature.
The apocalypse hadn't just unleashed the dead... it had also freed the monsters hidden in the hearts of the living.
Osamu watched in silence from the second-floor window, arms crossed and his mind a whirlpool. Outside, the sun slowly set behind the dense forest that surrounded the mansion, tinting the sky with orange hues. It was a beautiful view... but also deceptive. The calm was only superficial. Within those walls, the tension was so thick it could be cut with a knife.
He knew he didn't have much time.
—What am I supposed to do now...? —he murmured to himself, not expecting an answer.
Leaving the refuge was practically suicide. The cities were infested with zombies, and the roads were just as lethal. Not because of the dead, but because of the living. In this new world, humans were as dangerous as the creatures that crawled out there.
But staying wasn't an option either.
The guards were armed. Assault rifles, pistols, tactical knives... even grenades. Who in their right mind would want to face them in a direct confrontation? They had the strength, the weapons... and now, also the initiative. If they decided to act tonight, Osamu would have no way to defend himself. They'd throw him out forcefully, leave him in the middle of the forest like an unwanted dog... or worse.
And although he didn't fear for his life as much as he had before, he couldn't help but think of the girls.
They didn't know everything he knew. They hadn't seen how one of the guards gave Nino a lascivious look when he thought no one was watching. They hadn't heard the low laughs, filled with intent, that slipped through the radio when they thought no one could hear them. Osamu had. Because he had been paying attention, always a step behind the threat.
And now it was clear: if he didn't do something soon, he would lose them. All of them.
He wasn't a hero. He had never considered himself one. But even an ordinary man has his limit. And Osamu had just reached his.
He knew he couldn't beat them with brute force. He didn't have military training, weapons, or reliable allies. But he had something else: his brain. His ability to analyze, to think coolly, to find an exit where none seemed to exist. And above all, he had a silent, almost dangerous determination that had been born deep within his soul when he saw the only people who still mattered to him in danger.
So he began to plan.
If he couldn't beat them by force... he would defeat them from within.
...
—This place is really amazing. I don't think we'll need to leave it ever again —Ichika commented with a serene smile, as she reclined on the couch and let out a long sigh of relief.
Her words, though full of optimism, weren't naïve. Ichika was a fan of cinema, especially post-apocalyptic thrillers. She knew better than anyone that refuges rarely lasted forever. But still... this house had something different. A sense of stability that made her want to believe, even if just for a little while.
—Isn't it? Just having electricity makes it feel like paradise —Nino added, visibly happy while holding her phone in her hands. Although the social networks were down, she could still play a couple of offline games and look through her photos, small distractions that kept alive an illusion of normality.
—All thanks to Rias-san. Thank you for taking us in here —Yotsuba said with a genuine smile, her voice full of gratitude.
—Don't mention it —Rias responded from the other corner of the room, her tone kind but firm—. After all, Osamu's friends are my friends too.
The girls were gathered in the main lounge, under the soft light of a solar-powered generator that hummed gently outside. Among them, the conversation flowed naturally, sprinkled with soft laughter and light jokes. Occasionally, some serious remarks about the state of the world would surface... but those words would quickly dissipate, as if they were too heavy to hold for long.
Perhaps it was a defense mechanism. Pretending everything was fine, that this wasn't the end of the world but just a prolonged vacation. After all... they were still teenagers. Although stronger than they appeared, they were still young people trying to stay afloat in the middle of chaos.
Osamu was sitting nearby, in a chair by the fireplace. He listened to the conversations and occasionally participated, making subtle remarks or responding with a smile. From the outside, he seemed as calm as the others. As if he shared that same feeling of hope.
But inside... the storm was constant.
He knew what the others didn't.
He knew that the guards who guarded the refuge no longer answered to Rias, that their eyes were increasingly filled with greed and contempt. He knew their whispers weren't part of paranoia... but clear signs of betrayal.
And worst of all: he knew who they planned to expel first. Him.
The girls continued laughing. Rias drank her tea with elegance. And Osamu... smiled. Because someone had to. Because very soon, that refuge they all loved would cease to be a paradise.
But as long as he had breath, he wasn't going to let them touch them.
Not while he could stop it.
...
—Good job today too, Tatsuya-san. And you guys too —Osamu said with a friendly smile as he approached the front entrance, where the guards were making the shift change. Night had already fallen over the refuge, and with it, the night rotation began.
—Heh, after all, someone has to keep this place safe, right? —Tatsuya replied with his usual confident smile. Too confident, perhaps.
—It must be exhausting having to do this every day —Osamu commented casually, though inside, every word exchanged was carefully measured.
—Well, it is. Every now and then, zombies appear in the distance and we have to deal with them... But other than that, it's no big deal. By the way, is the food ready? —Tatsuya asked, a gleam in his eyes that had nothing to do with hunger.
Osamu nodded.
—Yes, give me a minute. I'll be right back with the rations.
As he walked toward the kitchen, the guards remained silent for only a few seconds.
—Heh... I like that guy. Too bad he doesn't know what's coming —one of them said, laughing softly.
—Shut up, Yahiko. Do you want to ruin everything? —Tatsuya reprimanded him in a dry voice.
—Bah, sorry. But I just can't wait... Just a few more days, and we'll finally be able to "enjoy" that hot nurse —he added, licking his lips with an expression that could only be described as repulsive.
Tatsuya sighed and narrowed his eyes.
—Just keep your mouth shut. Bastards... If anyone ruins the plan, I'll kill them myself.
At that moment, Osamu returned with a metal tray. On it were five modest plates of rice with tuna, accompanied by a piece of bread.
—Thanks for waiting. Here's your food —he said with his usual relaxed smile as he handed out the portions to each of them.
—Thanks, Osamu. You can go give the others their share now —Tatsuya said without even looking at him, already focused on his plate.
—Sure, I'll be right on it. Enjoy —Osamu said, turning and walking away with calm steps.
One of the guards blew on the rice before eating and murmured:
—That guy is pretty nice, don't you think? I'm starting to feel a little guilty about having to kick him out...
—Don't be an idiot —Tatsuya growled sternly, not looking up—. There's no room for men here anymore.
The group continued eating, with low laughs and disgusting comments, unaware that, from the hallway stairs, a pair of eyes were silently watching them.
It wasn't fear.
It was calculation.
Then, the light flickered.
Just for a second.
But sometimes, a second is enough for things to change.
Without anyone noticing, Osamu had added something special to the food. Something that would make the guards fall into a deep sleep, unable to react when the time came. No one would suspect him, not now, not with his usual behavior, so calm, so friendly. But he knew what he was doing. Everything was under control.
...
Now, in the darkness of the basement, the guards were tied up, unconscious, unable to move. The sleep induced by Osamu was not temporary; it was a deep state. The effects of the pills, disguised under the taste of the tuna, had worked perfectly.
With the lights off, the only source of clarity was the lamp hanging above him, illuminating his face with an unsettling calm. The fallen men, tied up and vulnerable, were just pieces on a chessboard. And Osamu had played with mastery.
He showed no emotion. He simply had one fact clear: what remained to be done was just a formality.
In his mind, a simple phrase echoed as he watched the sleeping men:
—The end of the game is near. And I won't be the one who loses.