Lusus Naturae by SaintInfernalNeos

Words: 291k+

Link: https://m.fanfiction.net/s/12429589/1/Lusus-Naturae

( [Freak of Nature] When Kirigaya Minetaka and his wife Midori found a strange 'pod' in the mountains, they knew they should have walked away. When a confused and weird-eyed little kid came out, the feeling was only doubled so. But...he seemed harmless, and he made their daughter laugh, so really, bringing him home couldn't hurt, right? After all, what's the worst that could happen? )

So…here is this thing. Sorry, I know I should be writing the next chapter of Requiem Universus, it's just that, classes have been stressing me lately and I hit a block with some of the scenes. Then, listening to a song yesterday made me think of several movies and weird books I have read, and this idea exploded in my head, so I thought I could write it as my kind of April Fools' gift? Does that make sense? Anyway, so, yeah…here is the thing, hope you enjoy, or something OxO

Disclaimer: SAO and its characters don't belong to me, but to Kawahara Reki. If they did, I would make 'There is But One Ultimate Way' the official canon epilogue of the series so as to everyone could be happy.

Lusus Naturae (ˈLuːsʊs Næˈtʊəriː)

A freak, mutant, or monster. Also called: Lusus.

[Latin: 'Freak of Nature']

Prologue: What's the Worst that could Happen?

January 2nd, 2010. Fukushima, Japan. Somewhere in the mountains, 01:25…

As the car drove through the mountainous highway, Kirigaya Minetaka couldn't help but sent a small smile towards the half-asleep form of his wife, their baby daughter in her arms.

Midori had been trying to make little Suguha fall asleep for a couple hours now, so it was only natural that she was feeling so tired. After all, taking your 8+ months old baby in a travel 2 prefectures away from your home wasn't exactly the best, easiest or brightest of ideas, but the woman was simply too paranoid to leave her at home with Minetaka's father.

At the same time, though, Midori had really wanted to spend New Year's Eve with her parents, as this would be the first one the old couple went through after the death of his wife's sister and her husband in that accident months ago, something that had deeply shocked everyone.

Putting the grim thoughts out of his mind, Minetaka took a deep breath and steeled himself, ready to keep driving for at least a couple hours more. They would need to drive for the entirety of next day and probably need to stop at least 3 times before arriving back to Kawagoe.

Meanwhile, quite a distance away from there…and under the earth, things weren't going exactly well for someone else.

(Primary Containment Facility has been breached. Emergency Systems failing. Warning, for the sake of the environment, all specimens must be destroyed…)

If there had been any human down there, in the strange and organic-looking 'factory', they would have been unable to understand a thing of what was being repeated endlessly through the audio systems. Even so, for the tall and strange creature that was running through the burning and exploding area, it was like a mantra of insanity, its 6 lower limbs carrying it through the breaking rooms and collapsing hallways as fast as it could, pushing eye-like buttons and turning down limb-like levers in every single place he went through, its 6 red eyes reflecting panic.

He had screwed up beyond all belief, and now he had to hurry if he wanted to stop a potential Extinction Level Event from happening in this Fate-forsaken planet. After all, if even one of the experiments that he had been taking care of down there made it to the surface, it could spell catastrophe for the hairless apes that were the dominant species of 'Earth', and honestly, after almost 60 of their years watching over them killing each other in stupid wars, inventing television, creating works of art, their pathetic attempts at interplanetary travel, writing masterpieces and slowly killing their planet's atmosphere, he had kind of grown fond of them. It was like a live-action series, only everything was real and he got to see it without direct consequences.

…come to think of it, why had they stationed him to make such dangerous experiments in an inhabited planet like this? Yeah, the resources he could discreetly get from the surface helped, but still, his people should have thinking twice before doing secret operations on a planet where…

The creature's train of thought was interrupted when a triple-secured door blocked his way, his clawed 'hands' quickly working at overdrive to input the codes and open it. This was it, the last, and arguably most dangerous, of the specimens he had been tasked with developing and looking over. Every single other one had been already destroyed, but he couldn't risk 'X-K0940' getting to the surface. Even without an actual Programmed Protocol, that thing's abilities would be deadly enough to doom at least the entire country his lab was under at that moment.

Finally entering the room, the inhuman being allowed himself a moment to look at the enormous, almost the size of a truck, tank that rested in the middle of the chamber, directly connected to the ceiling and filled with a reddish liquid. The emergency light made it difficult to see the massive THING that rested inside, but the creature in charge of the facility could almost perfectly imagine the too many eyes, teeth and claws of the experiment, and the times he would be just so creeped out he would electrify the liquid to make it suffer and fall unconscious when he was sure the thing was watching him worki…

Too busy with his musings of his past, the inhuman being wasn't able to see the collapsed piece of organic ceiling that was in his way until two of his legs tripped over it.

With an inhuman squeak, the creature fell forward in a mess of limbs, slamming face-first upon the control panel set before the massive tank, pushing an improbable sequence of buttons by doing so.

(Extermination Protocol Engaged. Selective Cleaning of the Planet has been approved)

Head snapping up, the 6 eyes of the scientist/keeper widened in horror.

(Programmed Protocol 666 established on Launch Pod. Loading specimen…)

Even as he tried to stand up, the tank's ground opened and two halves of something metallic/organic emerged, widened slightly as the red fluid was filled with energy, forcing the creature within to twitch and compress wildly, just enough for the two halves of the small 'pod' to close around it.

"No, no, no, no…! What are the freaking odds?!" screamed the creature while trying despairingly to abort the process.

(Releasing Experiment X-K0940 to the planet's surfa…)

The last instants before the collapse of the lab and subsequent explosion consumed him and that room, just as he saw the tank's ceiling opening and the pod shooting upwards towards the surface, was that at the very least he could trust in the paranoid humans to try their best and kill the thing before it did too much damage.

Then, everything was engulfed by flames and nothing remained.

Incidentally, the explosion reached the quickly ascending pod, barely grazing it, but still enough to damage the systems programmed into it and make it spin out of control through the rock and dirt it had been excavating through.

Seconds later, Kirigaya Minetaka was unable to held back a scream as he gripped his car's wheel for dear life when a thunderous 'Boom' echoed through the mountain road, his wife fully waking up with a squeak and Suguha's small eyes snapping open as she started to cry, the baby's sobs being the only sound filling the dark mountains after whatever that 'explosion' had been ended.

Eyes wary, both adults exchanged a glance before what seemed like smoke coming out from somewhere within the woods, not even a hundred meters from the highway, caught their attention, apparently whatever had exploded being there.

It was more than strange, because just a glance towards the pre-loaded GPS revealed that there shouldn't be anything around that area for kilometers, and Minetaka had seen no signs about any kind of factory or building for over an hour. The most sensible thing to do would have been to call the authorities and then ride away, but…

"Minetaka, what are you doing?!" shouted Midori upon seeing the man getting off the car, even as she tried to calm the crying Suguha down.

"Someone may be hurt!" answered the man as he started a light spring towards the wood, sending one last look towards his wife. "It's okay, I'm just going to check, you wait here in the car and try calling for help!"

Not even a minute later, Minetaka was staring with a mix of confusion and bewilderment towards the strange…thing that was sprouting from the soil some 6 meters before him, in the middle of two trees that had been all but broken upon its explosive emergence.

It was slightly oval shaped, and the size of a big dog, not to mention that it seemed both metallic and…pulsating, as if it was some sort of egg from a sci-fi movie.

The sound of rushing and nearing cries behind him made the man turn around in surprise in time to see Midori gasping towards the object, still cradling their crying daughter in her arms.

"Oh my God…"

"Midori, what the hell?! Get back, it may be dangerous!"

"Ju-just wanted to tell you that I couldn't make contact, reception is horrible here and…what is that?"

"I don't know, but it would be better if we just get the hell out of…"

And that was as far as the man went before some sort of red 'light' exploded from the pod, covering everything in all directions, he and his family included, making them freeze in shock as they felt the strange phenomenon wash over them like some sort of supernatural wave.

For Minetaka, it felt as if something was looking through his very being and analyzing it cell by cell…

The moment was over soon, some strange and unintelligible sound coming from the strange…machine?

(G& OkY# *Ho?¿H…)

Suguha's cries intensifying coincided with the strange sounds suddenly coming aggressively from the strange pod. Like…flesh twisting and moving, and bones breaking and cracking.

(Yy&6u6$. 8?=0h. X-K09-.-.-.-)

The strange sounds were brutally interrupted by static, as if whatever machine was speaking had short-circuited and stopped working.

The 'organic' sounds ominously continued before suddenly falling silent 3 seconds later, though.

At that point, the man would have just grabbed his family and rushed back to his car as fast as his legs allowed him…if he had been able to, as the sudden 'steam' coming from the pod had left him paralyzed from the shock, the thing opening and…

…dropping what seemed like a black-haired little kid no older than 2 to the ground, the boy slamming face-first into the ground and releasing a pained grunt. Behind him, the man heard his wife gasping, almost walking past him towards the fallen kid if he hadn't stopped her by grabbing her hand, still looking warily at the absurd event.

Slowly, almost shakily, the 'kid' stood up. He was…very feminine-looking, but still without a doubt a boy, something that was easy to see thanks to the fact that he was naked. Not to mention that he soaked from head to toe, dripping water (Or something very similar to it), as he stared around with apparent confusion…until his eyes settled over the Kirigaya family.

Midori released a small gasp, even as Minetaka stared with a mix of fear and wonder.

The boy's eyes were two red slits, with his sclera being a golden yellow filled with black veins, but then he simply blinked while his gaze settled on the man, his eyes suddenly perfectly human…and the same bluish-gray color as his, same ones he had inherited from his father and that Suguha had inherited from him. Then, the little kid's gaze turned towards Midori, who hugged their daughter tighter to herself as, with another blink, his eyes turned the same dark black than hers, the unknown boy tilting his head as if pondering something, seemingly not having even realized the impossible change his eyes had gone through. Then, he tried to take a step towards then, making Minetaka tense and be ready to bolt it out of there…

…only for the kid to fall face-first to the ground again, hard. A shaking coming from him indicated either another grunt or that he was unable to stand again.

Blinking, all fear and tension gone, the man just stared in confusion at the scene. What was he supposed to do in this…?

"Mi-Midori, what are you doing?!" all but screamed Minetaka when his wife took another tentative step towards the 'boy', taking advantage of his surprise having made him let go of her, before he quickly hurried at his side. "You don't know…!"

"Ahh…gah…buh…?" turning to the side, the oldest Kirigaya almost jumped in shock noticing that the boy had managed to get on his knees and was now staring at them with a tilted head.

No, that wasn't correct. He was staring straight to the sill crying Suguha in her mother's arms, almost as if wondering what that sound coming from her was.

When the 'little kid' was suddenly beside them and peering towards his daughter, Minetaka not having even blinked when it happened, the man almost pushed him back from sheer shock…before the boy clapped his hands in a childish gesture, tilting his head once again.

Suguha stopped crying, the baby girl blinking while tilting her own head to the side, Midori lowering her arms a little almost subconsciously to let her see the kid just before them.

Idly, the baby reached out with her hand, making a curious sound.

In answer, the unknown boy made the same sound, reaching out and taking the just slightly smaller hand on his, squeezing it softly.

When his daughter started happily laughing, Minetaka realized he had been holding his breath the whole time. Also, the boy was now smiling too, happily laughing and clapping towards the baby before looking up at them and doing the same.

It was at that point that the 'pod' behind them seemed to decide it was a good time to melt, closing the 'hole' it had been protruding from with the process, dirt slightly collapsing to finish the job. Feeling even more tired than before, the man looked once again at the smiling little kid, then at his laughing daughter and at his wife, who was biting her lips and looking from him to the boy before them.

One hour later, Minetaka could already see the first lights indicating they were approaching Tochigi Prefecture, the first towns in the area being quite close. Worriedly, he looked at the backseat, where Midori was now sleeping, Suguha happily snoring in her arms…and the unknown little boy resting beside them.

No matter how one looked at it, this was NOT a good idea.

Then again, it couldn't be that bad…right?

"What's the worst that could happen?" – Unknown (Forever remembered as the biggest idiot in the Omniverse).

Things had been…pretty strange, after that night.

As soon as they arrived home, late the next day, and after explaining to Minetaka's grandfather that they had 'found a kid abandoned in the woods', they had bathed him (Though the boy seemed to dislike water a lot, for some reason), clothed him as best as they could without actual clothes for him and then done the logical thing and called the police to report how they had found a 'missing kid'.

The little boy seemed hardly affected, even if a tad sad (Though really, Midori seemed even sadder at that moment), when the police took him away to the city's orphanage after filing out a report with his description, hoping to find his family or, if this had been the case, who had 'abandoned' him. The married couple knew they wouldn't really find anyone, but obviously didn't say anything.

From then on, almost once a week at least, either he or Midori would go to the orphanage to check up on the boy, who was always ready to receive them with that smile that never seemed to leave his face. Sometimes his wife would even take Suguha with her, and Minetaka noticed that their baby daughter always came home laughing and in a happy mood when this happened.

It took three months before the police called off any active search related to the 'poor boy', who was left in the hands of the system. Of course, no one was really surprised when the Kirigaya solicited to adopt him, and it was not unknown for the people who stumbled upon cases like this to get attached to the 'abandoned kids' they 'rescued'.

During the following 4 months they needed to fill all the paperwork and make the arrangements needed to adopt him, they noticed some of the…'oddities' the kid presented.

First, he ate a lot. As in, the orphanage's caretaker was left utterly flabbergasted during his first weeks, when he would eat almost thrice what any other kid did for every meal.

Second, he smiled…and that was it. He never looked sad, or angry, or anything like that. He just kept smiling all day, occasionally laughing about something or another. This, for some reason, creeped out the other children at the orphanage, especially after one of the older ones had tried one day to tell him to stop smiling…and he, who as far as they knew couldn't say a single word properly, had answered him 'Why should I?' in the same childish Japanese the would-be-bully was using.

The older kid had then tried to drag him by the hair out of where he was sitting…but the strange boy had just stood there, unmoving, not budging an inch from his place or showing any sign of pain as the other boy pulled his hair as if his life depended on it.

Just. Smiling. All. The. While.

After that, none of the kids made any attempt of getting near him, but once again, the unknown boy didn't seem to mind at all. He seemed contempt with just walking around, eating a lot, and looking forward to when the Kirigaya would visit him.

Then, one day, the little boy was standing beside Midori and Minetaka, Suguha at his side in a small baby carriage and tried to reach towards him while he looked towards the man and woman as they finished filing some paperwork with the caretaker.

"So…I'm going home with you?" asked him with that childish tone of wonder.

"Yes…yes you are, dear." answered Midori while giving him a soft smile, showing him the paper they had been just filling, pointing towards the place where the name of the person in question should be. "I know you can't properly read it, but this here…"

"Ka…zu…to…" mouthed the little boy with a bit of difficulty, surprising both adults and the caretaker. "What's that?"

"…that's your name now…son." answered Minetaka while putting a hand on his head. "From now on, you're part of our family. Your name will be Kirigaya Kazuto."

After all, the man's wife had remembered, that 'Kazuto' had been the name her sister once told her she would give her son if she ever had one. Midori somehow thought it was fitting for the 'miraculous child' they had found.

"Kirigaya…Kazuto…" muttered the newly baptized Kazuto while tilting his head, looking towards Suguha and finally complying to her pleas by reaching out and grabbing her hand, the 1-year-old laughing happily as he did so. "…I like it."

And that was how boy gained a name and a new family…

"Wild animals aren't pets." – Unknown (Probably ended up mauled by a critter they grabbed from the street).

Years passed, and things were surprisingly normal for the new family. Even Minetaka's grandfather accepted his 'new grandson' with open arms, saying he was proud of his son and his wife for being such kind souls towards an abandoned kid.

Minetaka eventually was offered a job overseas and, after much reluctance, took it. The money would do them well, especially now that they were raising two kids, one of which ate over twice what a normal one should.

As time passed, and as she got a promotion in her work, it was easy for Midori to sometimes think that strange night had never happened at all. That Kazuto was just a perfectly normal kid, like any other. One that liked smiling too much, ate a lot and that hated bath time, but a normal boy nonetheless.

However, it was impossible to not notice the boy's 'quirks' from time to time.

Like that one time when a 4 years old Suguha was sad because she saw a kitty on the street and was unable to catch it, and he, worried had told her he would bring her a lot of cats to play with.

Then, he had taken her to the courtyard and clapped his hands, before making some weird noise, to his little sister's confusion.

When Midori arrived home that day, she almost had a heart attack when she saw their courtyard filled with cats of all sizes and origins, as if every single feline in kilometers had come to play at their house. And in the middle of it all, her children were happily laughing and petting them, Suguha thanking Kazuto for it all.

Then, there was the time when Minetaka's father decided to teach his grandchildren the way of the kendoka, both kids starting to get kendo lessons from the old man with all the enthusiasm one would expect from a kid their age.

It took Kazuto 'somehow' breaking 5 shinais before the man quitted trying to teach him kendo, wondering how it was that the little boy was so strong. Even so, he never seemed upset or bored, smiling like always, and cheering on his little sister as she kept up with her training, making Suguha actually get pretty intense with it, motivated to become a great kendoka.

A year after that, Minetaka's father died. Her husband took a long break from his work just to come to the funeral, and they left the kids with a babysitter before going together.

None of them was expecting to, somehow, find Kazuto there in the graveyard already, silently waiting as they brought his grandfather's coffin to bury. That was the first time they could remember seeing him not smiling.

They had to call the babysitter to tell her to calm down and that the boy had somehow followed them, even as she apologized endlessly saying that she only took her eyes off him for a second, Suguha's voice in the background asking if Onii-chan had 'found grandpa', like he had promised her he would do.

Minetaka and Midori exchanged worried looks at that. Being kids, they had tried to ease the pain by telling their children their grandfather was going to a far way place and that he would probably take a long time in coming back. None of them was expecting their daughter to ask her brother to find him…or for him to 'succeed'.

Kazuto was oddly silent all the way back home. Then, without saying a word, he rushed into the house and, after making sure Suguha was sleeping, went down towards the dojo.

That's where his father found him, staring in shock as the boy calmly went through every single kendo stance he could remember having once practiced with his father perfectly, then some that no kid should be able to do, that Minetaka knew he had only seen his father demonstrate, with such speed and accuracy that seemed inhuman.

When the shinai broke from the pressure, the little boy let him fall and, as he turned to look at his adoptive father, his eyes were once again like that.

Red and slitted, with a yellowish sclera filled with black veins.

The sheer hurt reflected in them, however, together with the tears, prevented Minetaka from feeling any fear at all

"Grandpa…isn't coming back, right, papa?"

Then, he had rushed to hug the man's legs, sobbing. That was the first time Minetaka remembered seeing his 'son' cry.

He would discuss the incident with Midori the next day, before finally being forced to return to his work with worry, exchanging a few words with Kazuto before going back again.

"Take care, son. And…take care of your mother and sister too, okay?"

"…don't worry papa. Nothing will happen to mama and Sugu." answered the boy while smiling again, his eyes shifting from their 'normal' way to those inhuman ones for an instant as he said that. "I will make sure of that!"

Minetaka didn't know if that been reassuring or terrifying. Probably a bit of both.

Months passed, with Suguha devoting herself more to her kendo training despite her grandfather's absence. Her brother always made sure to cheer her on happily to show his support.

Then, one day, she was practicing near their courtyard's pond…when she accidentally fell inside.

That day, Midori had to come home from work in a rush, called by the neighbors about some sort of 'water explosion' having happened in their courtyard. When she arrived, it had been to see several of her confused neighbors on her half-flooded garden looking at the empty pond, and her children huddled together under several towels, Suguha shaking and clinging tightly to an unusually serious-looking Kazuto as he patted her head.

When their mother asked what had happened, the boy had been the first to answer with a simple yet strangely sinister phrase.

"The bad water tried to hurt Sugu, so I hurt the water bad."

Then, for the first time in years, Midori decided to ask just why it was that her son didn't like water.

His answer was…ominous.

"It brings bad memories…of red water that hurt me everywhere, and six red eyes looking at me…"

"Cut, rip, tear, dismember and devour! Oh, my sweet freak of nature…" – Unknown (Probably someone with serious mental issues).

Nine years old Kirigaya Kazuto was walking back home from school, hand to hand with his little sister, who was telling him about what they had learned that day, even as he heard her with rapture attention.

Then, he had suddenly stopped, frowning with confusion as he looked in a seemingly random direction.

"What's wrong, Onii-chan?" innocently asked a confused Suguha.

"Someone is crying…Sugu, hold tight."

With a smile, as if was usual, the eight years old clung to her brother's back, wrapping her legs around his waist for 'security', as he had told her.

Kazuto started running a second later, faster than one would expect from a little kid, especially one carrying a girl just slightly shorter than himself.

Not even 5 minutes later, they were in a relatively big park, rushing through the trees and stopping near where a twin-tailed little girl was crying, probably no older than 7, if that.

Worried, Suguha had gotten near her first after hopping down from her brother's back, even as Kazuto looked from her crying face to the tall tree where a kitty seemed to be hanging atop one of the highest branches.

"He-hey, are you okay? Don't cry, please!" pleaded Suguha worriedly while trying to comfort the girl.

"Pi-Pina…got scared from a dog…and got in the tree…now he can't come down…" sniffed the crying girl while looking at them with quivering lips.

"…I will get him down." suddenly spoke Kazuto with nonchalant voice, making the younger girl blink and look at him, even as his sister looked up towards the tree, worried. "You will stop crying if I do, right.

"U-uh…? I…"

The boy didn't even give her time to finish stuttering before he jumped, easily grabbing hold of the lowest branch, which bent slightly under his hold.

Then, something happened to his hands, the skin around them darkening and shifting even as he threw himself upwards with utmost ease, under the gaping gaze of the no-longer-crying girl and the worried one of Suguha.

Pina the cat watched with a mix of fear and confusion as the supposed human finished pirouetting his way to his side, smiling at him happily before raising his hands (Wait, human hand weren't supposed to have…all of that, right? Or to be looking at him?) before happily clapping with them. The feline relaxed immediately before the once again normal hands grabbed him, hugged him against the boy's chest…and then he let himself fall down from the tree back-first, the cat's owner screaming in fear.

He crashed down.

The ground got hurt.

Kazuto didn't.

"Here…your cat." happily said the boy while standing up, his back and hair dirty with grass and dirt as he handed the meowing Pina to his wide-eyed owner, who grabbed him with a look of childish wonder.

"Ah…tha-thanks…uhm…stranger?"

"Oh…you shouldn't talk with strangers, that's what mama always said!" cleverly warned the boy before extending his hand. "My name is Kirigaya Kazuto! Now we're not strangers anymore!"

"…A-Ayano Keiko. Thanks a lot, Kazuto-san! And…uhm…"

"Kirigaya Suguha. I'm his little sister!" introduced herself the girl before pouting at the boy. "Onii-chan, now you're a mess! Quick, let's get going home so you can take a bath!"

"…do I have to?" whined the voice in a comically depressed voice, making Keiko giggle.

"Yes, you do! I know you don't like water, and I get how scary it can be, but that doesn't mean you can stop bathing! Don't make me have to bathe you myself!"

"Fine, fine, I will take a mean bath!" replied Kazuto with his own pout, crouching to let Suguha climb on his back again before smiling at the twin-tailed girl. "Have a good day, Keiko-chan!"

"Yo-you too!" shouted the surprised girl upon seeing them running away from the area at surprising speeds. "…sugoi…"

That night, Kirigaya Midori arrived home tiredly while shaking her head, wishing for nothing more than a cup of coffee and lots of hours sleeping.

The sound of something heavy crashing and breaking make her freeze in shock, though, the twin screams of her children that followed it making her rush upstairs as if her life depended on it, throwing open the room to Suguha's room.

"Kazuto, Suguha, what…?! OH MY GOD!"

There was…something going from one side of the room to the other. Something long, black, with skin that seemed like rock and filled with teeth-like spikes. And it had eyes. Lots and lots of eyes.

Fear gripping at her heart, Midori's eyes moved toward the thing's end, seeing how long and claw-like fingers were smashing through the door of Suguha's closet, having almost literally torn it apart. And, at the other side, as she had feared, was Kazuto, his arm having mutated into that thing and…and…trembling in fear while his little sister hugged him in equal terror, even as both turned to look at her?

"MOM!" they both shouted, and, to the woman's absolute stupefaction, all the eyes in that monstrous arm his son now had (Which were a scarily familiar red-slitted with yellow sclera, now that she realized) quivered with the same fear and relief in the boy's human ones as both children rushed at them and hugged her…well, half-hugged her in Kazuto's case.

"I…what…uh?" was all that came out of Midori's mouth, her brain still trying to reboot.

"The-there was a monster in Sugu's closet!" sniffed Kazuto…all his arm-eyes sniffing with him too, reflecting the same worry. "S-so she called me over to help…"

"A-and Onii-chan smashed the monster with his hand! Boom!" cried Suguha while making a gesture towards the boy's monstrous limb, even as it 'returned', reduced its size and once again mutated into a perfectly normal human arm, the girl apparently seeing nothing wrong with that. "Ca-can you check that the monster is gone?"

"I-I would, bu-but…I have to make sure Sugu stays safe!" excused himself the boy, clearly scared, even as their mother deadpanned at them, as if not believing what was happening.

Twenty minutes later, the 'monster' (Which resulted to be a poor rat that had been left in a state that Midori preferred her kids not seeing) had been disposed of and both children were sleeping in their mother's room, hugging each other for comfort while the woman looked over them.

Kazuto had turned his arm into some sort of abomination of nature…because he was afraid of a monster in the closet. Midori wasn't sure if she should laugh or cry at the irony.

Taking a deep breath, she decided to go down to get some coffee and call Minetaka. That was going to be a long talk…

The next day, Kazuto would receive a call from his father, where he would be told he shouldn't do 'strange' things in public. Confused, the boy would accept, though not really sure what he or his mother meant by 'strange'…

"If you have claws, wings, and spit fire then you ARE a dragon! Don't try to deny it!" – Unknown (Probably some racist bastard).

Eleven-years-old Kirigaya Kazuto hummed happily as he entered the post office of some out-of-the-way town out in the country, at least one hour away from his home in Kawagoe.

His mother had told him he couldn't go too far from home for his new hobby (The boy got and dropped them incredibly fast), collecting stamps, but honestly, she hadn't specified just how much 'too far away from home' was. Kazuto figured that, if he could return home in time for dinner, it meant that he wasn't too far away yet. Besides, he already told Sugu he hadn't found any new stamps in the post offices of the city and that he was going to look a bit farther to get new ones.

Still happily humming the opening song of one of his favorite anime, the black-haired boy skipped inside the small building, looking around in wonder and smiling at the sight of several stamps he had never seen before, happy to have brought the few yen bills he had saved lately for this. Giving a glance around, he noticed that, besides the attendants behind the counter, the only ones in the office were a woman and a dark-haired girl around Sugu's age, which he assumed to be her daughter and that was sitting on a bench beside the automatic door reading a book.

Ignoring the odd look the ten years old gave him, the boy skipped towards the counter, receiving a curious from form the woman beside him as he leaned forward and asked another of the workers for stamps, receiving amused smiles in answer.

Then, he blinked as his acute senses caught the sound of something, turning around to see a pale-looking man with a bag and a dirty cap on his head entering, almost stumbling, into the post office, the little girl from before looking at him with apprehension as he walked towards the counter…and violently threw the girl's mother to the ground, to everyone's shock, slamming his bag on the counter and getting a handgun out of it, which he quickly used to aim towards the terrified elderly worker before him.

"Put the money in the bag!" screamed the man, the spit flowing down his face indicating he was either very high on something or just extremely on edge for what he was doing. "Don't push the alarm, hurry!"

Tilting his head to the side, Kazuto was quite aware of everyone's heartbeats skyrocketing at the robber's order (And was that a second heartbeat coming from the belly of the young worker a bit behind the one grabbing the money? Uh, curious…). Idly, he noticed that the girl was staring at her mother with fear before once again looking at him, as if wondering why he wasn't reacting with fear himself to the situation or…

The elderly worker's hand slipped downwards. Eyes widening, the man started to pull the trigger…

And something so fast and thin that was impossible to properly see, black and sharp, filled with small eyes, shot from the boy's chest and cut through the gun just as the robber shot, the resulting detonation making everyone scream as the man let go of his now ruined weapon.

The little girl watched in muted shock as the tendril shot back into Kazuto's chest (Leaving a hole in his shirt as a result), none of the adults having properly realized what had happened as they were too busy staring at the robber.

"You shouldn't do that. It's dangerous." spoke the boy with an emotionless voice, STARING at the now wide-eyed man, who turned to look at him with fury and horror.

"Shu-shut the hell up, you damn brat!" snarled the man while punching the boy in the face, the woman still on the ground screaming as a result, even as her daughter threw her book away and stood up, ready to rush to aid the boy, her overprotectiveness of her mother triggering her impulse…

But Kazuto didn't even flinch and the robber screamed while removing his hand, feeling as if he had tried to punch a wall. Finally, the workers reacted, one of them pushing the alarm while two of the younger ones jumped at the pained, weaponless and confused robber.

Dusting himself off, the black-haired boy walked forward, ignoring the skirmish on the ground to help the dumbfounded fallen woman to stand, her daughter rushing beside them shortly after.

"That was dangerous. Are you okay?"

"Ye-yes…" shakily answered the woman, looking from the now restrained man on the ground to the kid standing there, clear incomprehension on her face.

"…how did you do that?" demanded the girl while frowning towards him, making Kazuto blink and look at her.

"…sorry, what?"

"The gun! You blew it up, with something from your chest! I saw it!"

"Shi-Shino, dear, don't be silly, there is no way he could do that…"

"But mom, I saw it, it's the truth!"

"Oh…yes, I did. What of it?" answered the boy with clear confusion, earned a shocked look from the mother and a triumphant one from the daughter.

"See?! So tell me, how did you do it?!"

"…I just did it, it wasn't anything weird, really." shrugged it off Kazuto under the confused stares of both women, one seemingly at a loss and the other clearly unsatisfied.

"Bu-but…that's not something normal people just does!"

"…really?" the black-haired boy suddenly seemed confused at her words. "I …had never thought of it that way. Sorry if it bothered you, Shino-san, Shino-san's mother."

"A-ah…no, uhm…you see…"

"Hey! Who said you could call me by my name! Use my surname, I don't know you at all!"

"…but I don't know it."

"Asada! Asada Shino!"

"Ah, okay…then, later, Asada Shino-san, Miss Asada. I'm Kirigaya Kazuto, and I need to buy stamps!"

With those words, the boy happily walked to the counter, grabbed the stamps that had been forgotten there, left a bunch of yen bills and walked out of the post office, ignoring the outraged/ shocked stares of Shino and her mother, and the shouts for him to come back from the workers.

When the young girl rushed out of the building after him, intent on making her tell her how he did that, he was nowhere to be seen, much to her shock.

Sitting on top of a train going back to Kawagoe, Kazuto was too busy staring at his new stamps, while also wondering if he was somehow 'weird'…

"Veritas Vos Liberat (The truth shall set you free)." – Jesus.

Taking a deep breath, Kirigaya Midori steeled herself for what she was about to do. She had spoken with Minetaka yesterday, almost one hour arguing with her husband on the phone, and they had finally agreed that it was time to tell the truth.

Entering Kazuto's room, she wasn't surprised to see the twelve years old sitting side by side with his sister as he helped her finish her homework. Most siblings at their age started to drift apart for one reason or another, but honestly, their mother thought it would be a cold day in hell when she saw those two acting like normal kids.

"Ehem, Sugu, Kazuto?"

"Ah! Hi mom! Look, Onii-chan and I just finished solving a bunch of problems!"

"Sugu is really smart, mom!"

"Tha-that's great, uhm…Suguha, can you go to your room for a bit? I need to talk with your brother."

Confused, the younger girl looked from her mother to her older brother before shrugging, giving him a peck on the cheek before grabbing her note and rushing out of the room, Midori quickly closing the door as she exited it.

Kazuto felt tempted to tell her Sugu was just pressing her ear at the door, but decided against it. He didn't lie to keep secrets from his little sister, so he simply straightened on his chair and looked at his mother in confusion.

"Is something the matter, mom?"

"…Kazuto, dear…there is something I need to tell you, but please, don't take it the wrong way." taking another deep breath, Midori gathered her courage before speaking again. "You…are not our real son…"

At the other side of the door, Suguha's hand shot to her mouth, even as the boy's eyes widened at hearing her heart skip a beat.

…Sugu hadn't known? Really? He could swear she…oh, damn.

"Mom…I know I'm adopted." he spoke with sincerity, slightly surprising the woman, biting his lips as he stole a glance toward the closed door. "But…I don't really care about that, you're still my family, and…"

"I…am glad you think that, you don't know how much, but…there is more." looking to the ceiling, apparently lost, the woman once again glanced at her adopted son, finding the conversation extremely hard to continue. "…do you remember anything before the orphanage? Anything at all?"

"I…I'm not sure…" muttered the black-haired boy while looking to the side, suddenly seeming…very confused. "I…I remember red water that hurt everywhere sometimes, but…that's all…"

"Son…you know how you can do things…that other kids can't do?" now, Midori had Kazuto's full attention, his unnervingly eyes fixed on her. "The truth is…a bit over 10 years ago, I, your father and Suguha were coming back from visiting my family, and…"

Behind the door, a lost and confused Suguha tried to understand what she was hearing, though her mind unable to accept it. Her brother…wasn't her brother? And he had…come from under the earth?

She had seen a lot of movies with him, scary ones at times. She knew that things that came from under the earth were usually bad news, but he always told her he would protect her from anything, even if he was scared too…so…why…?

The sound of his mother screaming Kazuto's name broke her out of her shock, the young girl throwing the door open in time to hear a window being smashed.

Midori rushed towards the window, even as a scared Suguha looked at her back.

"Kazuto! Kazuto, come back, please!"

"Onii-chan…? No, Onii-chan, don't go!"

Ignoring the shouts for him to come back, the confused boy kept running through the night, scared, worried, wanting to cry and not knowing what to do.

"What am I?"

That was the question that ate him all night as he jumped to rooftops, easily scaling walls and going through parts no kid his age should be able to.

He had never stopped to think about it, not too much, but the words of that Shino girl came back to his mind now that he knew how his family had really found him.

He wasn't normal. What was he, then? A monster? An alien? A creature from another dimension?

Kazuto was still lost in thought even as the sun started to come out, idly aware of the tears on his face as he kept moving, stopping atop what seemed like some fancy mansion before jumping again, staring at the sky.

He raised a hand, almost wondering he could touch the heavens by reaching far enough.

Then, he blinked, remembering that he couldn't actually fly and that he hadn't bothered to look where he was jumping now…which was straight into a big pool.

"Oh…nononono, AHHHHH!"

With a thunderous splash, the boy sank in the water like a rock, shaking his arms around like mad and trying to get out.

In her mind, the water was suddenly red, and it hurt everywhere, even as six red eyes watched him with a mix of curiosity and repulsion.

Bad. The water was bad! It was going to hurt him! He needed to get out, out, out, ou…!

A floating ring was thrown over him. Eyes widening, Kazuto grabbed it, bringing himself out of the water and gasping for breath, shaking and soaked.

"Air…no water…need to get out…out…"

"He-hey, are you okay?!" shouted an unknown voice, making the boy blink and look up in wonder at the scared-looking girl at the edge of the water, probably his age, which was one of the cutest girls he had ever seen.

The chestnut-haired girl, for her part, was terrified. She had decided to take a break from studying for her next important exam and come to gaze longingly to their house's pool, knowing that her mother wouldn't let her swim until it was summer when she had suddenly heard a scream and an unknown boy had literally fallen from the sky before starting drowning. Panicked, she had grabbed the nearest floating ring and thrown it his way, relieved when he had grabbed a hold of it.

Worriedly, she motioned for him to come to the edge, which he clumsily did so, before she got him out of the water, noticing how he was shaking and pale.

"Tha-thanks…you sa-saved me…"

"O-okay, relax, alright? I'm going to call Haruka-san, uhm, our housemaid! Sh-she will give you something to dry yourself…uhm…"

"Kazuto."

"Right, Kazuto-kun. I'm Asuna, s-so take it easy there, and…eh…I don't want to worry you, but your eyes are kind of red and yellow…"

"Oh…sorry." looking down, the boy blinked again, the change in his eyes reverting. "I didn't mean to scare you…"

"Of course you scared me; you fell down from the sky and almost drowned in my pool!" shouted the thirteen years old, much to the boy's shock, before shaking her head. "Just…stay there, okay? Haruka-saaaaan!"

Half an hour later, Kazuto was sitting awkwardly on a couch in the fanciest living room he had ever seen, wearing clothes too big for him and being repeatedly asked if he needed something or was feeling sick by Asuna, under the amused look of her older brother, Yuuki Kouichirou.

"Your mother is coming to pick you up, Kirigaya-kun. She sounded extremely worried." commented the young man with a small smile. "Honestly, how did you even get into the house, let alone fall into the pool…?"

"Onii-sama, I already told you, he fell down from the sky!"

"I-I did…sorry, Yuuki-san, I didn't mean to cause trouble to any of you…"

Shaking his head with amusement, Kouichirou found funny that his sister would still stick with such childish prank. Maybe she wasn't as much the mature teenager she told him she was, not that he really believed it.

Oh well, at least this hadn't happened when their mother was home. Knowing her, she would have terrified the kid to death before even calling his family.

"…wait, you ran away from home?! Why?!"

"Be-because…I don't know…I didn't want to scare my family…"

"Well, now you have certainly scared them, running away and almost drowning! Honestly, what kind of boy are you?!"

"I-I'm sorry…snif…"

"…wa-wait, are you really crying?! So-sorry, I didn't want to be so mean, s-stop!"

Barely holding back a chuckle, the young man wished he had a camera. Seeing his little sister off the rails like that was certainly amusing.

A bit later, when the boy's family came for him, he would see Kazuto walking sadly towards them and saying he was sorry, only to be told the same by his mother even as his crying sister almost strangled him to death with a hug.

Then, Asuna would tell him to never do something so stupid again and apologize again to his mother and sister on his behalf, drawing an embarrassed shout from Kazuto and giggles from the Kirigaya women. Though Suguha frowned her way when she held her brother's arms and make him swear to really not repeat something like that.

All in all, he could say it had been an eventful evening…

As the Kirigaya's car drove away from the Yuuki residence, the silent Kazuto (With his sister possessively hugging his arm and sending looks back towards the fancy house they were leaving behind).

"…mom…Sugu…aren't you…scared of me?"

"Eh? Why would we? Onii-chan is Onii-chan, no matter what!"

"Yes, as Suguha said, Kazuto. Even if you aren't…normal, you're still my son. You're still part of this family, and that's not going to change. Sorry if the conversation yesterday made you think otherwise, I just…thought you needed to hear the truth."

"No…sorry for overreacting, mom. And sorry for worrying you, Sugu. I promise…to never do anything stupid like that again."

"Good."

"I'm glad to hear that, Onii-chan…"

"…I probably should promise to not use a tentacle to break a gun again either…or does doing it to save someone justify it?"

"I don't kno…wait, what?! When did you use a tentacle (You have tentacles?!) to break a gun?!"

"Ah…over one year ago, I think? When I met Asada Shino-san and her mother…"

"Who is Asada Shino?! Onii-chan, what have you been doing behind my…I mean, our backs?!"

"Ouch…Sugu, stop, don't pinch my cheeks, it hurts!"

"Lies! I have seen you falling off a tree without blinking, back when we met Keiko-chan! I know this doesn't hurt you!"

"Wait, hold on a second, what have you two been doing without telling me?!"

And so, the day continued for the slightly unusual family…

Deep within the mountains of Fukushima…a clawed hand sprouted terrifically from the earth.

Then, it took almost fifteen minutes for the coughing and clearly winded creature to emerge from the dirt, killing any terrifying effect as he looked around.

"Fucking finally! It took me years to regenerate myself and then get out from the labs remains, but I'm here. Thank Fate I was able to survive…" groaned the creature in its own inhuman tongue, his six red eyes scanning the surrounding area while standing unsteadily on his six legs, before dragging an organic-looking 'box' from the dirt after himself. "Now then, let's see…wait, this can't be right! It says X-K0940 is still alive…but there are no worldwide reports of panic or chaos or the end of the world?! What the hell?! Ugh, no matter, I will take this improbability as a blessing! I need to do my job, find that abomination…and exterminate it." those words said, the creature morphed the strange box into an oversized weapon, loading the cartridge with a heavy sound as he aimed to the sky. "As Waryum, the caretaker of the Primary Investigation Facility on Earth, I swear to save the primitively stupid yet amusing mankind from that unholy spawn!"

Heroic declaration made, the so-called Waryum rushed forward in a brave sprint.

He promptly slammed into a tree, breaking it, and decided that maybe he should just walk while trying to save mankind.

Author's Notes: Well, that was that. Thank you all for bothering wasting your time reading this oddity XP

In case it wasn't clear yet, Lusus Naturae means, literally, 'Freak of Nature' in Latin, and I thought it was an oddly appropriate title for this story that basically went off the idea of 'What if Kirito was some sort of Eldritch Abomination…but had no idea he was one?'. Adding that to my weird and crazy imagination and humor, that some of you already know, gave birth to this…thing you have read.

If anyone is wondering, all the background events of the SAO Universe were the same as canon in this AU except that Midori's sister never had a child. And that, you know, someone thought it was a good idea to let an idiot in charge of dangerous experiments under Earth's surface. After that, well…you can see how this little Kazuto has already started to mess with the plot.

Also, I have no intentions of continuing this story right now, Fate knows I shouldn't be adding more when I have yet to finish one and I owe everyone the sequel of another, but if I did the plot would basically center around our dear not-so-normal idiot trying to grow up as normal as he can, and obviously failing, while the great Waryum hunts him in hopes to 'save mankind'. Add the SAO Universe's plots in the middle…and you get a nasty mess.

As a certain elf-demon would say "You're not prepared." Only that the 'you' would be almost everyone trying to fuck up with people, from Kayaba to Sugou to etc…if anyone is interested in adopting this idea, though, write me about it!

Well, that's all for now, I guess. Have a good day, hope you haven't been pranked as much as me :P

Till next time, this is Saint, signing off!