Summary: Put one eighteen year-old med student 3700 years into the future, and you'll have said grumpy student maiming the first thing that ever so moved in his sight. Unfortunately for the tiger, its fur now serves as his cloak. Whoever said that Biology sucks?

Warnings: Future Slash, Slight AU, OC-Insert, Mention of OCs, Pseudo-Medical Knowledge (I only rely on Google, okay? Don't believe everything I write here), Trigger Warnings, Isolation, Slight Case of Schizophrenia, Voices in the Head, Simply Put OC is Not Okay, Animals Galore (no animal was hurt during the writing of this fanfic), Language, Canon Typical Violence (which is few and little in between), etc.

Disclaimer: I literally know only 6% of what Senku is saying and making.

When Tora saw the green light, his first thought was, "Fuck, Jason's ramblings about aliens are real—"

Then he couldn't move, couldn't keep his eyes open, couldn't breathe and—how the fuck is he still alive?

It's that last sentence that kept him awake, kept him going even though he's sure he blacked out for a few minutes (hours? Days? Years? Decades—?), because there was no scientifically correct reason why he's still alive and breathing when every system in his body save for his brain has shut down.

There were some moments when he could hear Professor Hugo's nasally voice discussing about the biology of the human body, and how the biology of animals' are actually not far from theirs.

"This proves that Darwin's theory about humans descending from apes have some merit to it," he would say, mustache twitching and blue eyes sparkling with a mad scientist's gleam. "But we still haven't found the missing link! The process and stage of how animal became the homo sapiens!"

Tora adored that stout man, reminding him of another small professor in a book stacked in his prized bookshelves. Jason can bemoan about too many terms to memorize and too many steps to take during Prof. Hugo's class, but Tora loved every second of it.

(And maybe he's a bit hysterical now, maybe he's slowly losing his mind because it's so quiet and he's all alone where was he help mE—)

He exhausts his brain, exhausts his mind, his thoughts and all of the knowledge he has. He thinks about the latest anime Katie will surely be rambling about as soon as she got her hands on a subbed version (and no amount of begging will let him translate whatever episode it is, even if he likes it), thinks about Mom's tea parties with the neighborhood ladies and he'll most definitely be dragged into because he's such a polite young man, thinks about Jason waving another magazine about UMAs in his face as they debate about its existence and where they would be, thinks about how he's so empty even though his thoughts are still so many and fast and he'll never find the off switch to it at this rate has never found it even when he was small—

Then something cracks, both literal and not (was it his sanity? Had it finally given up on him?), and he sees the sky for the first time since (forever—).

A brown leaf falls to his face (he still can't move his mouth and nose and how is he breathing—!?), and a look around shows that the trees are of the same shade and color, dotted with reds and oranges and a part of him (which? Which? They've all been scattered to pieces and he can't find them all—) knows it's Autumn but has there been this many trees before—?

More cracks (and they fall down down down down—) reach his ears ("Don't worry about it, it'll be fun—"), and he can move (there are binds on his wrists, binds on his legs and he doesn't want it doesn't want it nononono—) but the air is so (hot, why is everything so hot his blood feels like lava—) cold and he shivers (aches, because it hurts so bad and he wants Jason to hold him and save him and Katie to talk—) because he's nake(d and where are his clothes who is this man and everything hurtshurtshurts—) and red fills his vi(sion and white noise—) and—

Something moves in his peripheral, and Tora pounces.

—

He blacked out again (how many times has it been, how many days had passed—?), and there's a cloak made out of a tiger's fur wrapped around him, the furs where limbs should be tied across his chest as the hinds pool around his ankles from where his legs are against him.

He tries counting backwards with no specific order, tries to breathe like Katie showed him to (gods, he wants Katie to talk and talk and talk because her voice is like home and she's not here oh god why—?), and it helps just a bit, makes everything less blurry and everything will be alright, Tora. Katie's here to—

(Katie's not here—)

Tears burn his eyes ("It's okay, mate, let it go."), and a sob chokes his throat. He pulls the tiger skin closer to his weak body (so weak, so weak, if you hadn't been weak you wouldn't have been tou—) and cries his heart out, missing the two warmths of his friends (anchors, soulmates, his reasons of—) sandwiching him and he ignores how the moss underneath him is too thick, ignores the moon shining down on him, ignores how everything is suddenly too bright and he needs to hide his eyes—

The lower jaw and blood and flesh has been removed, but the head of the (deaddeaddead) tiger covers his face and that's all that matters.

(He dreams of large hands and smooth palms holding his sweaty one tight, and it breaks and makes his heart all the same when he wakes up alone).

—

Whatever those aliens had done to the world (and he's 100% positive they're aliens, or else he won't be able to face Jason ever again), they've practically reseted everything and cleared it all out like a new file in a game.

Tora had the dubious pleasure of running into more than five wild animals (is he near the zoo or something!?) everyday, and it's making his building a tree house slower than ever.

So he looks for and creates tools like he's living the fucking Minecraft dream.

(Ohmygods, it is a Minecraft dream what the fuck—)

Armed and ready (with the knowledge that he'll have something else to fall back on), he all but tackles the ruling wildlife that had never seen a human-slash-tiger before they can react.

(Of course he doesn't kill them. Even a fucking alien invasion won't stop his damn bleeding heart)

—

A few weeks later (he's taken to marking the passing dates with lines like he's in some freakin' prison movie) sees him having clothes to wear along with his tiger skin cloak, still barefooted and feeling a bit silly wearing a skirt but dismisses it for practicality.

There are a lot of fruit trees near the far south of where he'd set up camp at (also the same place where he woke up, 'cause he's sentimental that way), and a lake is at the east side of the forest so long as he doesn't stumble upon a bed of snakes again (he promises never to tell his friends about that day once he finds them, because he will find them. He didn't survive an alien invasion just to not let Jason have his fantasy come to life!), and he's doing pretty well for being all alone.

Of course, his isolation strikes every now and then (and he hates the black outs, hates waking up to unfamiliar places with dead animals around him and he's scared out of his wits—), and he has to write on another tree trunk to keep track of the dates, and he keeps going because Jason and Katie are waiting for him dammit he can't get distracted now—)

The statues terrify him.

Gaping mouths, wide eyes, bodies frozen in time (like he used to be, and why haven't they woken up yet—?). He passes them by everyday while scavenging for food, sees the deers and wolves (they avoid him, and he avoids them) sniffing and wondering what they are.

He ignores the statues, ignores the new faces because he doesn't know them and he doesn't want to think about what their broken arms and legs mean even when his brain connects the dots (and he sees a dead man once, sees a dead man and his only consolation is that he doesn't know him) and his stomach flips at it all as he pukes his breakfast to the nearest shrub he could find without disturbing the animals.

Ah, right. The animals.

His only companions, his only friends. The ones that make him feel less lonely despite not being able to talk.

He tended to an injured raccoon once, maroon fur matted with dirt and his paw twisted painfully from his apparent fall. After a dozen scratches and bites, his wound is all wrapped up and now he has a furry companion perched on his shoulder always. He had named him Aito.

Then he sees a baby snake, a white boa if he remembers correctly, and he scoops her up hurriedly since it was nearing Winter and wears double the clothes he had crudely made as she nestled around his waist. She was given the name Selene weeks after she refused to slink away when it was already Spring.

Then one by one, more animals decide to approach him. Some injured, most young, and all of them wary but hopeful. He takes them all in, allowing them access to the clearing where he had woken up, and soon he has all sorts of visitors dropping by at a daily basis.

Chipmunks fill the gaps of his treehouse's walls with nuts and acorns, possibly as a thank you for saving their young. Wild boars bump into his tree trunk, eagerly waiting for his head pats. Turtles living on the lake he frequents float up to greet him, the other water animals doing the same once he'd clean some of the leaves floating on the surface on a whim.

Two years pass by, noted by how many Autumns he's lived, and his clearing now looks like Dr, Doolittle's very own place, swarmed with animals and filled with chitters and tweets and snorts.

Tora sees them all from his branch where Aito sleeps at his lap. He feels not so alone now, and he allows a smile to grace his features just this once.

(They can't talk, but they didn't need to because them staying says it all).

—

His second Summer is punctuated by a howl too close for comfort, and three grown wolves cutting his way to look for food.

Aito snarls with his tail high up in the air, and Selene pokes a head out to flick out her tongue warningly. Both had grown for a year, and Tora strangely feels no fear at the face of three carnivores that can rip him up to pieces.

(Maybe it's because he's been existing amongst so many animals that he notices their lack of aggression, their tails down and chins slightly bowed and eyes not quite meeting him)

"What's wrong?" he asks, voice husky and rough from months of disuse, not seeing the need to communicate vocally with his friends unless they were going to do something stupid. Like say jumping up and down on Gertrude's stomach while she was in hibernation.

The middle wolf whines, low and deep. His ears flicker and he points his muzzle towards a direction, and soon all six of them are following towards the sound of paws crunching leaves and whimpers breaking the tense air.

Tora's eyes (hidden and shadowed and only curious little Aito has been granted permission to see them) narrow at the circle surrounding a fallen wolf, aged and larger than anyone else. A pup was whining incessantly at his snout, tiny and heartbreakingly sad.

The wolf from before pushes him towards the middle, but Tora shakes his head.

"It's too late," he replies, eyes hooded and shoulders slumped. "He's far too old and sick for me to help, ookami."

As if understanding his words (and he wouldn't be surprised if they could, or at least get the impression of what he meant), the wolf howls into the setting sun. And the others join him, loud and ringing and grieving. The pup joins too, high-pitched and tapering off into short hiccup-like sounds.

Tora should be leaving, should be letting them mourn privately for their fallen kin (their Alpha? Their eldest?), but his feet are rooted to the ground, and his stay is made for him when the pup crawls into his lap and keens.

—

The pack of silver wolves (for their fur is too light to be grey, and too dark to be white) move their territory somewhere nearer to his treehouse, and Tora is pretty sire they consider him now as their new Alpha, orange and black stripes be damned.

Aito is unsure of their newest neighbors, and Selene had hissed at him comfortingly when he bites his lower lip in worry.

The pup is a new addition to his entourage, nipping at his footsteps and yipping for his attention. The wolf (the very same who had looked for him and howled first), whom he had dubbed Fenrir, sometimes tagged along, usually to keep an eye on his younger counterpart, but otherwise followed him with the same finality as Aito and Selene had exuded when they first came along.

(Tora is amused at them all, but accepts them without protest as always)

Scavenging is now taken care of the wolves—well, the older ones, that is. The pups and youngs (the 'teens', as Tora had labelled them) were left to either stalk the surrounding woods or play with the other animals (as soon as they got over their instinctual fear and saw Tora taking care of them), and it still amazes Tora whenever he sees the pups playing around the giraffes, when he sees the crocodiles (he doesn't even notice them joining their little group) letting numerous birds of different colors perch on their backs, and it brings water into his eyes and

—

"God, you would've been stoked to see this, Jason," he whispers to the air. Aito looks at him curiously, head tilted.

He smiles and shakes his head, and approaches the family of four-and-two-leggers with serpentine bodies and snouts and fangs and—and it kind of feels like home.

(There were no beige walls, or fluffy comforters, or striped pillows with Jason and Katie bouncing on the bed like toddlers on a sugar high, but it felt safe and warm and he's finally home after two long years)

He puts another line among the others, another day passing with him being the only human.

(But he's not alone anymore, and his black outs are lessening. He's learned how to survive and exist and live)

Tora may not be the smartest, or the strongest of survivors here on Earth, but that's okay.

(Besides, who needs brains or brawn when you can have animals?)

—

Tora remembers a time when he was Tora Watson, exchange student from Japan and utterly confused and new to Manhattan.

Jason had pulled him in, then, waving him over before the professor had even come in the lecture hall, with his curly blonde locks and bright, bright violet eyes.

Tora remembers his blue shirt, his grey hoodie and red pants with white converse highs bouncing up and down in place.

His first thought was that he was a child, full of energy and innocent.

(He's not entirely wrong, but he's not entirely right as well)

Katie joins them during the third semester, coming from another class and had just changed her ATM course to take extra classes like Psychology and Chemistry, something that baffled Jason to no end.

(With her curly ebony hair and hazel eyes, along with her denim jacket and white top paired with brown shorts and black boots, Katie had shot back, "Well, not everybody likes numbers like you, doofus."

Jason was adorably bemused)

There were other friends, some Asian, some Spanish, always young and dumb and with so many big dreams that they look like the cast from a cheesy TV series.

But Jason and Katie were always there, laughing and smiling and screaming and crying.

They were there when he had forgotten his Philosophy homework due yesterday, they were there when he had flunked his first Biology exam (and god was that week despairing), they were there when he went to a cinema for once, they were there shouting their lungs hoarse with him on the rollercoaster Tora would forever regret riding, they were there when he took his first drink at a club, and they were there when he woke up bruised and aching and nononononono—

("HOW DARE YOU—!"

"—ason, stop! We need to—"

"Tora, can you—"

"—e hurt him, Katie! He—")

It was common knowledge that when Tora or even one of them were seen, the others were right behind them ("But what about if we're sick or away?" "Then we'll be with you in spirit." "Jason, no—").

And even if they're gone now, they won't be much longer. Tora will make sure of that.

He and everyone else in their not-so-little Sanctuary will search until the ends of the damn Earth if needed.

(Like Katie had jokingly referenced more than one time, "Ohana means family, and family never leaves the others behind.")

—

Kohaku had been picking some foxtail millets for Senku and the others when she saw it, and even then she couldn't believe her own two eyes.

There was a flying dragon in the sky!

"… Senku," she started, and the sorcerer—scientist, he had corrected, but Kohaku could never remember for the life of her—looked up at her from where he was cleaning the foxtail millets. "Senku! Look!" He and Chrome looked up, and she could see the moment their eyes widened in realization.

"That's a dragon!" "Is that a kite!?"

Chrome and Kohaku blinked. "A what?"

Senku dismissed them for now, standing up to his full height with intense eyes, foxtail millet ramen forgotten for the very familiar and from his own time kite that was flying freely in the sky.

It was a long, train-like kite made up of other kites, with a larger one as the dragon's 'head' and yellow ribbons serving as its tail. The dragon was red and intricately done, something that only someone who had seen an example could do. And even if it was crude and ugly and misshapen, the fact that the kite was made out of something eerily similar to paper would've raised flags in Senku's mind.

"This…" he grinned, wide and with too many teeth, eyes shining. "… is exhilarating!"