Disclaimer: I do not own Naturo or One Punch Man

Plot bunny = more commitments.

Sasuke will be somewhat OOC.

Genos will sound a little robotic at the start, but he'll soon open up to Sasuke and show his humor.

Author's Note: This story takes place right after the Uchiha massacre.

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Chapter One

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He's waking up in the hospital one moment - sobbing, terrified, choking on something hot and wet and salty ohGodit'srushinguphisthroat - sunlight streaming through the windows, catching his eyes on the reflective glass, and - then he's lying outside his family's house. Staring up at the stars that burn in the abyss of the night sky.

…What?

He doesn't move.

I'm going insane.

Sasuke feels his head shake while something in his mind hums like his father's copying machine about to print.

[Your assessment is somewhat incorrect] a Voice tells him. Monotonous and droning. [Asset-san has been diagnosed with Depression and Post Traumatic Stress Disorder. Sensei – current whereabouts unknown. Friendly reminder: "DO NOT PANIC" - has advised calling people who have mental illness 'insane' is insensitive and rude. Asset-san's assessment of himself is self-abuse and should be reassessed for future wellbeing to himself and others]

…right.

[Due to Asset-san's unstable influx of emotion and being underage (also going off of past intelligence that Asset-san has repeatedly demonstrated his unreliability to take care of oneself) Mission Override was put in place. You have a twelve o'clock meeting with Therapist Yamanaka Inoichi-sama tomorrow evening. You're welcome.]

There is no fear or panic as Sasuke sits up and stands. Padding back inside and passing the stain where to him, not seconds ago witnessed his older brother slaughter their parents.

There is nothing but detachment. An exhaustion in his chest that no matter how deep he breathed didn't seem to release.

He doesn't stop until he's face down on his bed and cocooned in his blankets. Somewhere in the back of his mind, the voice of his father tells him to man up a shinobi shows no weakne -

There's a whirring in his head and his father's voice fades.

Sasuke's heard of genjutsu turning people mad. His mother's sister killed herself after the Third Shinobi War. She was held and tortured by the enemy for weeks. He doesn't know what they did to her exactly – doesn't want to know - only that when she was finally rescued and admitted to the Hospital she 'broke'.

Did Itachi break him?

[Excluding thin laceration on cheek, Asset-san has received no physical wounds]

Sasuke hugs the covers around him and tries to ignore the silence taking place of his family. Tries to pretend that everything is just a bad nightmare and he'll wake up anytime now.

10…9…8…

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The Voice introduces himself as Genos, a cyborg that died protecting Earth and his sensei - [whereabouts unknown. Friendly reminder: "DO NOT PANIC"] - from an invasion of monster toads.

His hallucination is very creative.

Genos denies being a hallucination.

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His first therapy session goes like this...

He was training, ignoring Genos berate him with facts and figures when he hears the words "Mission Override" and in a blink he's sitting in the waiting room of the hospital. Split knuckles bandaged and wearing freshly ironed clothing. Smelling faintly of body wash instead of sweat.

At the time he doesn't allow himself to panic, at the time he doesn't allow himself to think and fear the daunting – oh ever daunting fact that maybe he doesn't have complete control over his body. That this hallucination could take over whenever he wishes. Do whatever he likes -

But was it a hallucination – or something more sinister; a creation of Itachi's own madness? An implant of some kind? Like the ones used in wartime, to turn him into a spy and -

He doesn't recognize his body tingling, adrenaline rushing and laboured breathing until the words "Mission Override" vibrate like an earthquake over his thoughts again. And in a blink he's back home.

In a house painted with memories and bloodstains.

His first therapy session goes like this…

Sasuke never turns up.

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Two days after Sasuke hears a voice in his head that wasn't his own, Iruka comes nocking at his door with the work he missed out on along with what they are learning for the rest of the week.

All Sasuke does is stare up at Iruka's kind, sort of saddened smile, half-listening to Genos's disturbingly accurate assessment of the man.

"I'll come back with next week's work if you don't feel up to returning anytime soon, ne, Sasuke-kun?"

He nods and sure enough, days later Iruka is back.

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Looking in the mirror, Sasuke is barely able to hold back a flinch. Eyes dart away, expression flashing horror for a split second before twisting into a mixture of hatred and fear (the latter of which he will deny).

To the ANBU watching in the shadows - corners of the house painted with memories and bloodstains never quite cleaned - they will see a beautiful boy with a small face, big eyes and tussled hair reminiscent of a scruffy cat. They see a broken boy, one in dire need of a hug (God, they think. Has he even been hugged since the Massacre?)

What they don't see –what they should see - is a glimpse of something behind the eyes. Something that, if anybody looked for too long, would unsettle them like a spider crawling up their bedroom wall. Something calculating and observant. Something that glowed a faint toxic yellow around the blackness of Sasuke's iris.

Out of the dark it saw.

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Sasuke knows they're watching him.

The ANBU who were too late to save his Clan. The ANBU who let Itachi get away. The ANBU who couldn't get a simple couple of blood stains out of wood.

He can feel their eyes on him, examining every move he makes. Almost like they were waiting for a reason to pounce and throw him into a place where people hear voices and loose time. Almost like they were waiting for Itachi to show up – making Sasuke think Itachi was going to show up.

Genos tells him paranoia was expected for people suffering from PTSD and he shouldn't be afraid.

Sasuke tells him to shut up.

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[Our star constellations are very different.] Genos's voice hums thoughtfully, vibrating his mind. How does he do that? [Since being here I've been attempting to pinpoint my exact, or at the very best estimated location. Given the lack of similar constellations I question whether I, or some no-good being, misplaced myself on another planet in another galaxy...]

Sasuke blinks up at the vast lights, and asks the question that has been terrifying him for weeks.

Did Itachi put you here?

[The boy who hurt Asset-san?]

Yes.

[Unclear.]

Sasuke bites his tongue. Taking that as a 'no'. Genos makes a whirring sound of affirmation.

…Are you lying?

[No.]

But how could Sasuke possibly know that?

[I am unable to lie to Asset-san.]

Uh…Why?

There was a second's pause.

[…Asset-san and I are one. I see no reason to lie to my host.]

That was ominously vague.

Clarify - and why do you call me Asset? I have a name.

[When general Boil dropped me 60,000 feet above sea level, my consciousness was somehow transported through space and time…] despite Sasuke's valiant attempt, he's unable to follow the next few sentences. Which is frustrating given the chance this voice is a product of his trauma meaning he should be able to understand. Truly, his hallucination just gets weirder every day. [I woke up as a prepubescent homosapian -]

Startled, Sasuke sits up.

You mean you weren't human before?

There is a stuttered pause, the kind someone makes when they're aimed with a stupid question.

[I was.]

Uhh –

[I was a cyborg. Born human but for revenge and justice I became something more. Half human, half artificial. The limbs I lost in the attack that took hundreds of lives were replaced by machinery to give hope for not only myself, but for others as well. In my quest to avenge the slaughter of my family and others – to defeat Evil I sacrificed my body. To accomplish my goal, I am prepared to do anything.]

Above them a meteor burns upon entering Earth's atmosphere. Shooting across the sky in a stream of light. Sasuke watches it, Genos's words swirling his thoughts and for the first time since the massacre of his Clan, the terror of a foreign Voice in his head – Sasuke feels something akin to companionship. An understanding so deep his chest aches.

[…you have been listed under the title Asset-san because you are one.]

Sasuke shakes himself back into alertness.

Repeat that - more clearly.

[You are an Asset to get me home.]

Confusion was a friend Sasuke dearly wanted to get rid of.

I don't know how.

[This world holds science and the mystic arts as one. Given time I am certain we will find a way. Saitama-sensei left me with his coupons, I must get back.]

Sasuke stays silent, not knowing how to respond to that, because –

- because Genos is an elaborate hallucination manifested by trauma.

Nothing more.

He lies back, silent and watching the stars.

...Oh, he forgot to make a wish.

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Genos proves himself useful when Sasuke begins more strenuous training.

[From the data collected during Asset-san's recovery period, you should expect a 20% decrease in power. Do not be disconcerted, through proper training and a healthy diet Asset-san's power will return to normal levels in a matter of weeks.]

All Sasuke can do is stare dumbly at a random training post for a couple of seconds, considering something.

Really, he was nothing but a voice in his head. A delusion made up of his consciousness.

Still, couldn't hurt…

"Gen – " he stops, mindful of ANBU.

Genos, you said data collected. Is there more?

[Affirmative.]

Could you tell me more? For instance, my average score on hitting the training post point blank five meters away is 5/5. Estimate what it would be if I did it now.

Genos doesn't so much as stutter.

[Going from data, 3/5. Below average.]

Father would be disappointed.

[A week or two of proper training will return you back to average.]

A week or two.

Out slithers a memory, of Itachi coming home from a mission in stitches; arm having gotten almost slashed open, blood levels dangerously low. Yet he could maintain his average.

Sasuke's fist clenches.

[Why are you comparing yourself to somebody who killed your Clan?]

He flinches but says nothing. Twirling the kunai in his hand, Sasuke takes a moment to reacquaint himself with the feel of the grip. The weight of the metal. The sound of it slashing through air.

He throws.

And misses.

Genos whirrs in his mind, as though humming in thought. [Your stance is slightly off…]

Off to the side and hidden high up in a tree just behind him, an ANBU with a Cat mask cocks her head when Mission Objective shifts his stance. Eyes far away and nodding as though listening to someone that wasn't there.

.

It takes five weeks before Sasuke and Genos decide it was high time to go back to the Academy. Five weeks before Sasuke is no longer afraid of the humming inside his head (not that he'll admit he ever was afraid). Five weeks before Sasuke semi-trusts Genos and the cyborg's advice.

Five weeks to come to an agreement about body snatching.

[Body snatching?] Genos had asked, sounding somewhat disgruntled about Sasuke's assessment.

What do you call it then? Sasuke had grumbled in a mixture of anger and exasperation.

[Protection. Whenever Asset-san experiences emotional distress, or is too overwhelmed by a situation I temporarily take over and put you to sleep so you have time to mentally heal. Humans, especially children, are fragile]

Sasuke didn't, and still doesn't, know what to say to that. He's not used to people other than his mother being so…kind. Caring. It just a shame that it had to be Sasuke's own hallucination to give him something he so desperately missed.

So instead he had asked…

But don't people suspect anything?

Call it a hunch, but Sasuke had a distressed feeling that Genos is not what people would call 'average'. If Sasuke could picture his delusion, he would think Genos would look like a Hyuuga (unpleasant) and act like a brick wall.

The loud whirring in his mind told him Genos had taken offence to that.

[From gathered intel I am able to replicate your mannerisms]

And Sasuke was back to being disturbed by his hallucination again.

Alright, just…don't do it unless I tell you to.

Which he planned on never doing. At all.

[Asset-san has unhealthy tendencies, cannot comply with order]

He couldn't stop the snarl that escaped him.

It's my body!

[Learn to share. Mission Imperative states to protect Asset-san until I return home]

A growl vibrated the back of his throat, "Geno -!"

[If you don't want me to take over your body then learn healthy habits. Take better care of yourself, or I will]

All right, so they haven't completely cleared up the 'body snatching' issue just yet. But they were working on it.

One argument at a time.

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When the week begins and Sasuke heads off to school, something occurs to him. He's at the entrance of the Compound and staring up at the looming wooden doors.

That he hasn't opened in weeks.

Genos never did make another therapy appointment after hearing Sasuke's vehement denials of going. The cyborg was probably waiting for him to come around (and yes, Sasuke had thought of going when Genos told him he'd stop 'body snatching' once Sasuke starts showing he could take care of himself).

All the groceries are delivered by hand via ANBU – and when was that decision made? – all the breakfasts miraculously appear when he's awake. Every meals are pre-made and wrapped in the fridge. Even the house stays clean. Everything he needs done was always taken care of before he even got to worry about it. And it's not like he has any friends to hang out with…

The thought of leaving the compound, getting away from bloodstains and memories and ghosts have never occurred to Sasuke.

He was just…not all there, he supposed after consideration. He felt no desire to get away. Which is odd, he thinks. Recalling times when he couldn't wait to get out of the house and go explore.

(Nii-chan I found a bunny in the forest the other day! Shisui-nii-chan say's father wouldn't allow me to bring it home but -)

All he really thought about lately was revenge – something he's having a stupidly hard time dealing with, where to start? Where to start? - and Genos.

Which is even odder.

His world of mother, father, Itachi and the Clan. All so big and bright and happy – had abruptly shrunken down to two people. One not even here, probably out somewhere killing pleasant people and ruining their day. And one actually not here.

Hmm.

Was it bad that Sasuke didn't actually care?

[Unknown]

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Astonishingly enough, Genos was more uncomfortable about the stares than Sasuke was. He would have found that almost amusing if the damned cyborg stopped sounding like he was releasing steam.

Should I pour you an ice bath or -

[Asset-san exposed to too many potential threats, calculating safer routes…]

Alarmed, Sasuke opens his mouth to shout but it's too late.

[Mission Override]

In a blink he's outside the Academy.

[Discovered safest route and downloaded it to memory. For now on it will be Asset-san's new course.]

Sasuke doesn't bother to argue, knowing it would be useless. Besides, he can't deny he's a little relieved. Can't deny that during the first two minutes of stepping outside of the compound, he hadn't imagined somebody – maybe Itachi in disguise slipping out of the crowd like air and striking like a tornado. Because while ANBU are quick, they were deceived by Itachi once, who's to say they wouldn't be again. And sure ANBU are swift, sharper than a katana's edge, but they wouldn't want casualties – that would hinder them. Slow them down. Allowing Itachi enough time to slice his neck like he did with mother and father. Finish the job he meant to do. No second thoughts this time, no siree.

[Those thoughts are illogical, Asset-san.]

He also can't deny the comfort he gains from somebody reminding him that.

(It's just a shame that it's his own hallucination doing a job the adults should be doing)

.

Iruka takes one look at him and smiles brighter than he has done in weeks. His peers take one look at him and all movement ceases. As though somebody had pressed the pause button and Sasuke was the only one left in motion. For a couple of seconds, Sasuke wonders if this was a good idea.

Then a boy named Kiba enters the room, gapes at him and slaps a hand stronger than Sasuke had originally thought, on his back. It would have nocked him down in a second flat had Sasuke not been training rigorously with Genos.

"About damn time!" Kiba barks and Akumaru appears from the boy's hoodie with what sounded like a friendly yap. "Would'a thought ya turned into a hermit, Sasuke-kun~"

Like the first raindrop in a storm, more beckons. People scurry over to him, eyes wide and expressions sneeringly curious. He can hear the beginnings of personal, private questions. About his family, about his brother, how many people were killed. Even the newborns? Even the babies? Your cousins? Did they really get beheaded? Did you see it? How much blood was there, I heard the street ran red! How did it feel? Why did he spare you?

Why are you still alive?

There are worse things in life, Sasuke tries to remind himself when the herd of ill-intending children nears, Itachi could be here.

[Mission over – ]

"Genos," he hisses under his breath. A churn of shame mixed with determination burns his stomach. If he can't deal with his classmates, then he shouldn't be a shinobi.

You heard that right?

[…self-assessment logical but I don't like it. Your heart rate is above normal and indicates high-levels of stress and anxiety, if you continue to hyperventilate -]

Blocking Genos out takes a lot of effort and he feels as though he should be applauded, considering it's his own mind he has to silence.

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Thoughts? Feelings? Please review :D

Every word helps.