The Gastrea were a blight upon the world, categorized by a terrifying hierarchy of threat: Stage I, Stage II, Stage III, and Stage IV. With each successive stage, their size swelled and their defenses thickened, becoming so resilient they could shrug off direct missile hits. Furthermore, as they grew, they absorbed genetic factors from all manner of organisms, causing them to evolve into bizarre, unpredictable forms. It wasn't uncommon to see a Gastrea with the carapace of a beetle, the tentacles of a squid, and the wings of a bat. This chaotic evolution meant many Gastrea possessed strange and dangerous abilities.
But Stage V… Stage V was an exception among exceptions. Normal Gastrea that reached Stage IV were generally considered "complete," their evolution halted. A Stage V, however, was something else entirely—an ultimate form, a calamity given flesh. Only a handful of people in the world knew the true, horrifying origins of these beings.
They all shared one common, undeniable characteristic: they were impossibly, monumentally large, like kaiju straight out of a tokusatsu film. Even the most massive Stage IV Gastrea was insignificant next to the sheer, mountain-like bulk of a Stage V. To avoid being crushed under their own immense weight, their muscles, skin, bones, and internal organs were all supernaturally reinforced, rendering them immune to almost 100% of humanity's current arsenal.
These Stage V Gastrea were codenamed after the signs of the Zodiac. There had been eleven confirmed global sightings, and they had displayed cataclysmic combat power in the great war ten years ago. These twelve Zodiac Gastrea were the kings that had once brought humanity to the very brink of extinction. Without exception, they all possessed hard Varanium exoskeletons immune to conventional weapons, the most powerful regenerative abilities, and a complete immunity to the Monoliths' suppression field. On top of that, each one boasted a unique and devastating special ability.
To date, there were only two successful subjugation records in all of history: Taurus and Virgo, eliminated by Initiator No. 1 and Initiator No. 2, respectively. These victories were nothing short of miracles, fleeting sparks of hope in an overwhelming darkness.
Therefore, if such a being were to appear in the Tokyo Area… it would mean a devastating disaster. A complete and utter annihilation where virtually no one would survive.
"…Things just got a whole lot more complicated," Yotsuba Mahiro muttered to himself, the words leaving his lips in a cloud of condensation in the chilly night air.
After arriving at the unexplored territory outside the Monolith barrier via the transport plane Kisara had arranged, he found himself standing in what could only be described as a primeval forest. The moment his boots hit the damp soil, a wave of impatience made him run a hand through his hair in frustration.
Towering, ancient trees grew in a lush, dense thicket, their canopies blotting out the already weak moonlight. With it being the dead of night, visibility was terrible. A heavy rain had fallen a few days prior, leaving the entire forest soaked and muddy; the air was thick with the pungent, earthy scent of decay and wet soil.
But this was no natural wilderness. Here and there, like ghostly skeletons, were traces of human civilization long abandoned: buildings choked by thick vines, structures blanketed in moss and climbing ivy, and the rust-eaten frames of cars, their glass and tires long gone.
The most crucial point, however, was the feeling of being watched. The moment he landed, he felt them—countless pairs of eyes probing him from the deep, oppressive darkness between the trees. Pairs of crimson orbs, glowing with malevolent light like demonic searchlights, radiated an intense, primal hostility. They were filled with a singular, unified desire: to tear him apart and crush him into the mud.
"Well, this is one heck of a welcoming committee…"
As soon as the words left his mouth, Mahiro's arm blurred. A Varanium dagger whistled through the air, flying straight toward one of the closest pairs of crimson eyes.
SHINK!
The throw was like a starting pistol. The slumbering forest awoke in an instant. Strange, guttural roars erupted from the darkness, followed by a chilling chorus of answering cries that echoed through the trees.
With the simultaneous activation of Multiple Observation and Sharingan, Yotsuba Mahiro's vision pierced the gloom, finally revealing the true forms of the monstrosities surrounding him. It was a large army of Gastrea, ranging from dog-sized Stage Is to hulking, vehicle-sized Stage IIIs. They lurked in the branches and behind the trunks, encircling him in layered, tightening rings—a siege of fangs and claws.
"Haaa~ How scary. A dark forest and all that~" he sighed, the sound dripping with sarcasm.
But the sigh was a signal. In the next heartbeat, an intense, swirling psychokinetic light erupted from his body, illuminating the dark forest in flashes of brilliant blue. The very air crackled with power.
Along with the churning dust and debris, a killing mist of ice exploded outwards. The temperature plummeted. White, glittering frost raced up tree trunks and branches, hanging from the leaves like crystalline jewelry, glistening under the sporadic moonlight. In an instant, the world around him was dyed in a deadly, silvery white.
He walked calmly through the swirling ice crystal dust that danced around him like a galaxy of frozen stars.
Dust to dust. Ashes to ashes.
His figure was that of a silent reaper of ice, equally freezing and harvesting all life that dared approach. Even if the chilling mist alone couldn't completely freeze the tougher Stage III Gastrea, the flickering arcs of raw psychokinetic energy that followed swiftly granted them a merciful release.
.........
"Don't move!"
The command, sharp and high-pitched, came just as he dispatched the last of a particularly stubborn Stage III. The cold, circular muzzle of a gun was pressed firmly against the small of his back.
"Tell me, girl," Mahiro's voice was deceptively calm. "Do you think your finger will pull the trigger faster, or will I turn around and cut your head off faster?"
From the distinct shape and feel pressing into his spine, it was a shotgun. Judging by its height and angle, his assailant had to be a Cursed Child. While he held a deep-seated pity for these girls, that didn't mean he would endlessly tolerate them pointing weapons at him. Normally, Cursed Children who worked as Initiators wouldn't harm other Promoters, but there were always exceptions—rogues like the late Hiruko Kagetane, who twisted these children into ruthless killing machines.
Therefore, determining her allegiance was his top priority.
"…Under normal circumstances," the girl's voice replied, steady but tense, "a finger pulling a trigger is faster than someone turning around and swinging a knife."
"Is that so? Well then… let's give it a try~"
Whoosh—!
In the very next instant, the world seemed to slow down. With a silent mental command, an acceleration spell flared around his feet. His hand was a blur as it flew to his waist, drawing a fresh Varanium dagger in one fluid motion. He spun on his heel, the blade slicing through the air in a deadly, silver arc aimed directly behind him. There was not a single moment of hesitation, no quarter given.
But then, a fraction of a second before the knife could meet its mark, both he and the girl pointing the gun at his back froze solid, locked in a tableau of mutual surprise.
"Why… is it you?"
Mahiro's body reacted before his mind could fully process it, his muscles screaming in protest as he wrenched his arm to an abrupt, jarring halt. The razor-sharp edge of the dagger came to rest gently against the girl's neck, not even touching her skin. Yet, the sharp air current displaced by the blade's incredible speed ruffled her light golden short hair, cleanly severing a single, silken strand that drifted slowly to the forest floor.
Under the pale, filtering moonlight, he could now clearly see the girl's full appearance. She wore a simple, almost fragile-looking long-sleeved dress paired with practical tight pants—an outfit completely unsuited for the deadly wilderness of an unexplored area. In her small hands, she clutched a massive, intimidating firearm: a large-caliber, fully automatic shotgun with an under-barrel grenade launcher, a distinctive model produced by Shiba Heavy Industries.
But the most defining feature was that blank, nearly expressionless face, like a porcelain doll.
Who else could it be but Senju Kayo!
"Ah…" the girl murmured, her large, amethyst eyes blinking slowly. "It's that strange big brother who can read minds."
'Strange big brother who can read minds'? What kind of ridiculous, nonsensical title is that…? Mahiro felt a vein throb in his forehead, a retort already on his lips. But the words died before they were spoken. His sharp eyes, honed by countless battles, noticed a subtle detail: Senju Kayo's arm, the one holding the heavy shotgun, was trembling almost imperceptibly.
And at her wrist… a vicious, jagged wound, as if bitten by a large beast, oozed a steady trickle of blood, staining her sleeve a dark crimson.
"If you don't intend to shoot, then you might as well put the gun down," he stated, his voice firm. This wasn't a suggestion.
As if on cue, Senju Kayo's finger, which had already left the trigger, went slack. The heavy weapon dipped towards the ground.
"Hmm…"
After a long moment of silent thought, the girl finally chose to lower her gun completely.
"Good. A wise move."
"..."
Facing his praise, the girl did not speak. She merely stared at him with those wide, unnervingly calm eyes that seemed to hold a deep, empty ocean within them.
"How about we talk somewhere else?" Mahiro suggested, his tone softening a fraction. "You look like you could use some rest, don't you? And I have a feeling you probably have a lot you want to say."
"Hmm."
That was the second word the girl had uttered tonight.
However, just as Mahiro turned to lead the way, a small, surprisingly strong hand tugged at the sleeve of his jacket.
"What's wrong?"
"I'm injured," Senju Kayo stated, holding up her bleeding wrist as if presenting a factual report.
"I know that. And?"
"So, please let me go ahead. I will clear the path for you," she declared with an unnervingly calm demeanor, her voice a flat monotone as if all emotion had been discarded into the cold night air. "This is the most logical strategy I can formulate given my current condition and our objective."
It was said without a hint of fear or resentment. She spoke as if she weren't a wounded child, but a disposable tool offering to act as a human shield. The composure she displayed was far beyond her years, reminding him faintly of Asaka Mibu's stoicism, yet this was different. Asaka's calm was born of discipline and loyalty; she would never view herself as a mere instrument. Even her sacrifices were made as a person, with conscious will.
But before Mahiro could respond, Senju Kayo had already shouldered her automatic shotgun and begun walking forward on her own, a small, determined figure ready to face the darkness.
Looking at the petite back marching resolutely into potential danger, Mahiro said nothing. He merely fell into step silently behind her, his senses stretching out once more. His Multi-Observation surgical procedure activated, painting a detailed mental map of their surroundings, while his Night Demon remained on a hair trigger, ready to erupt at the slightest threat.
...
The journey was surprisingly smooth; they encountered hardly any formidable Gastrea. The occasional Stage I or Stage II that lunged from the shadows was efficiently dispatched by Senju Kayo with a precise, brain-shattering blast from her shotgun. It had to be said, the physical mobility of the Cursed Children was astonishingly high. Even injured, and even if she wasn't a combat-specialized type, she could move with a fluid, powerful grace, leaping onto the heads of larger Gastrea to deliver the killing blow point-blank.
Their destination was a fortress-like relic from a bygone era. It was a small, stone-built bungalow, its long, narrow windows strategically facing downwind. The entrance was barricaded with weathered sandbags, and the surrounding area was littered with abandoned heavy weapons and overgrown trenches. It was clearly a defensive position left over from the Gastrea Great War ten years prior.
Inside, the two of them lit a small, cautious fire in a rusted metal drum. The flickering flames cast dancing shadows on the stone walls.
"Do you want coffee?" the girl asked suddenly.
After receiving an affirmative nod, she rummaged in her pack and pulled out a compact water heater and a jar of instant coffee, beginning the methodical process of boiling water.
Illuminated by the firelight, Mahiro took out a roll of clean bandages from his own gear. "Your turn. Let me see that wrist."
After she silently offered her arm, he carefully cleaned and disinfected the jagged wound, his movements surprisingly gentle for someone who could wield a blade with such lethal speed. He then began to wrap the bandage slowly and securely. The scene was bizarrely peaceful—two individuals from opposing IFA pairs, on a high-stakes mission, yet it felt for a moment as if they were on some strange, melancholic picnic.
"Alright," he said, finishing the bandaging and tapping the back of her hand lightly. "The bleeding's stopped. Your Gastrea virus erosion rate hasn't spiked this time, but if you get injured again, you might not be so lucky."
"Mahiro-san is truly a strange person…"
After learning his name, Senju Kayo handed him a steaming mug of brewed coffee. She then continued, her voice still flat, "Not only do you help me, who should be your enemy, but you also help a dirty Cursed Child like me bandage her wounds… even though I had a gun pointed at you just a while ago."
"But you didn't intend to shoot, did you?" Mahiro replied nonchalantly, taking a sip of the warm, bitter liquid. He poked at the fire with a stray branch, sending a shower of sparks upwards. "Otherwise, we wouldn't be sitting here so peacefully now." A mere gun wasn't something he took too much to heart.
"That is precisely why you are strange," she insisted. "Normally, if a Cursed Child points a gun at someone, it wouldn't be an exaggeration for them to be killed on the spot. After all, we are tools… tools that can be consumed and discarded at will." She paused, her head tilting slightly. "Could it be… that Mahiro-san is the legendary lolicon?"
Pfft—!
Mahiro nearly choked on his coffee. "…That's going way too far," he complained, a look of utter speechlessness on his face as he raised his head. When his gaze met Senju Kayo's, he noticed for the first time a flicker of something—a faint, almost imperceptible glimmer of amusement—in her otherwise utterly placid eyes.
"It seems you're doing quite well if you have the energy to make fun of me," he shot back, a wry smile touching his own lips.
"My apologies." Sasha promptly lowered her head in a formal bow, but then immediately added, "However, you don't seem to dislike us Cursed Children."
"Why would I dislike you?" Mahiro's expression softened as he stared into the flickering flames. "In my eyes, you're no different from any other child. What's more… you didn't choose this life. Who can choose their own birth? Those people who hurt you, the ones hiding behind the excuse of avenging the Gastrea… they're not heroes. They're just cowards, bullying beings they perceive as weaker to make their own miserable selves feel strong." He poked the fire, sending a cascade of embers skyward. "Honestly, that kind of behavior is just… pathetic and disgusting."
Hearing him say this, a look of profound disbelief dawned in Kaya's wide, amethyst eyes. Ripples of emotion subtly disturbed the vacant stillness of her gaze, and a slow, genuine smile—small, but undeniable—finally graced her lips.
"Indeed, Mahiro-san, you are different from everyone else…" she murmured, her voice gaining a sliver of warmth. "You really are a lolicon."
Yotsuba Mahiro: "..."
The first half of her statement had been fine, even touching, but the second half left him utterly dumbfounded.
Looking at her pretty face, delicately outlined by the dancing firelight, he couldn't help but retort, "You! You're just taking advantage of being a Dolphin Factor with an IQ of 210 to slander me, aren't you?! Be careful, or I'll really throw you out there to feed the wild Gastrea!"
"My most sincere apologies. Please do not do that. I am reflecting deeply," Kaya said, bowing her head again to the dark force of his empty threat. However, with her perpetually emotionless delivery, it was impossible to tell if she was being sincere or just continuing her deadpan act.
"But speaking of which," Mahiro continued, shifting the conversation, "where's that muscle-headed idiot partner of yours? Did he finally get himself lost for good?"
"Are you referring to Ikuma Shougen-sensei? We were separated," Senju Kayo explained without hiding anything, candidly recounting the events. Just like in the original timeline, she and the hot-headed Promoter Ikuma Shougen had been caught in a clever Gastrea trap and forced to split up. While this was undoubtedly a streak of bad luck for Senju Kayo, it was a fortunate turn of events for him. At the very least, it presented him with the chance to save this intelligent, high-IQ loli's life.
"Then what about your Initiator, Mahiro-san?" Kaya asked, her head tilting in curiosity. "The child I saw at the Ministry of Defense last time, she must be your partner, right? Did you get separated from her, too?" Her memory was photographic; she clearly recalled the serious-faced girl with the katana and how she had effortlessly defeated the high-ranked Hiruko Kohina. Logically, with such a strong fighter, combined with Yotsuba Mahiro's own monstrous power, the two of them shouldn't have been separated even if they encountered a Stage IV Gastrea…
"You mean Asaka-chan? I didn't bring her," Mahiro stated casually. "You should know, right? I'm a solo operator; I never bring a partner on missions."
"Even for a dangerous mission of this magnitude?" Kaya's eyes widened a fraction.
"That's right."
"..."
For some reason, Senju Kayo suddenly fell silent. She hugged her knees to her chest, curling her body into a small ball, making her already petite frame seem even more fragile and solitary. She stared blankly into the flames, her thoughts unreadable.
"Indeed… rumors are truly unreliable," she finally whispered, almost to herself.
"Rumors? About me?" Mahiro prompted.
"Hmm…" Kaya nodded gently. "There are many rumors about you circulating among the other Promoters. Even Ikuma Shougen-sensei, whose brain is quite literally made of muscles, holds a strong prejudice against you. He often says that fighting without an Initiator is a fraud's game. They say… you are a fake."
"And what about you?" Mahiro asked, his tone neutral. "Do you think so too?"
"No…" Kaya shook her head, her light golden hair swaying. "I think… you must be a very gentle person."
The girl closed her eyes and placed a hand over her heart, as if feeling for its beat.
"You, unlike the others, bear no animosity towards us Cursed Children. If I'm not mistaken, the child you call 'Asaka-chan' is likely a first-generation Cursed Child, just like me. But from her, I didn't sense any of the… tool-like conditioning that we are taught. Even when she stepped forward to shield you, it felt like an act from her own heart, a true desire to protect…" Her voice grew even softer. "Honestly… I'm a little envious of Asaka-san."
"Is that so?" Mahiro leaned back, supporting his weight with his hands on the dusty ground. "What I do is merely what any normal, decent person should do." He gazed up at the sliver of night sky visible through a crack in the fortress roof. "Moreover, having a little maid at home who can help with laundry, cooking, housework, and even warm the bed, and who only needs good food to be happy—that's the ultimate definition of a cost-effective dream life, don't you think?"
Even though, in his case, this ideal had already been miraculously achieved. Twice.
"Even though the sentiment is kind, you phrase it exactly like a lolicon pervert would," Kaya stated matter-of-factly. "Truly, you are in a class of your own, Mahiro-san."
"This time, I'll choose to take that as a compliment."
"It was intended as one."
Seeing his candid, unashamed demeanor, Senju Kayo's lips curved into another slight, real smile. Then, she softly murmured the conclusion she had clearly already reached:
"So, Mahiro-san… you really are a strange person."
Through the wide cracks in the crumbling, drafty bunker, a sliver of the night sky was visible. The perfectly full moon, hanging in the cloudless expanse, continued to radiate its serene, silvery light—a beautiful constant in a world that had long since collapsed into ruin. The moonlight itself was pure, but the earth it illuminated was utterly defiled.
It was a simple, cruel truth of this world: when a person consistently acts against the grain of society, even if their actions are fundamentally right, they will be branded an anomaly. A strange person. Though the principle was twisted, that was the unyielding reality.
They, the Cursed Children, were seen as tools, as monsters wearing human skin, as disposable killing machines by other Promoters. Yet, Yotsuba Mahiro treated them with something resembling… care. Honestly, a small, hidden part of Senju Kayo longed to know what that felt like…
Unlike the feeling of using a shotgun to kill one of her own kind. Unlike the visceral memory of shattering the skull of a little girl her own age with a point-blank blast. It was a sensation she had learned to endure, a necessary numbness for survival. But she truly, desperately never wanted to experience it again.
Kshhh—! Bzzt—!
Just then, a burst of static crackled to life from a black, receiver-like device placed beside Senju Kayo's meager belongings. A rough, familiar male voice cut through the interference.
It was Ikuma Shougen. The very same man Mahiro had once bluntly told to get lost.
Kaya immediately tensed. She was acutely aware of Ikuma Shougen's intense prejudice against Yotsuba Mahiro; the man had been clamoring for a chance to "teach that arrogant brat a lesson" ever since their last encounter. Letting him know Mahiro was here would only ignite a volatile situation.
With a swift, urgent gesture of her hand, she signaled for Mahiro to remain absolutely silent. She then picked up the radio, her small fingers deftly adjusting the tuning knob until the noisy signal cleared.
"--you alive… Hey! Hey…! Kaya! If you're alive, answer me, dammit!"
"It is good to hear you are also alright, Ikuma Shougen-sensei."
Picking up the handset, Senju Kayo responded with her characteristically serious and earnest tone.
"Of course I am! How could a few Gastrea do in someone of my caliber?! But forget that! I've got good news!"
Ikuma Shougen feigned suspense, but both listeners could easily imagine the smug smirk hidden beneath his signature skull mask on the other end. And they could already guess the nature of this so-called "good news."
After all, in a hellscape like this, there was really only one thing that could qualify…
"We found the little bastard who stole the briefcase!"