Snowflakes crashing against a glass window were such a peculiar phenomenon. One second, the snowflake's motion was unconstrained, erratic and carefree, drifting along the icy air flows, oblivious of gravity. The next, the collision brought together two entities that had nothing to do with each other in a way that was sudden, unexpected and irrevocable.

Hiccup's concern, however, was more down to earth, namely, the cold. At that late time of the day, the large and nearly empty laboratory room was absolutely icy. The University of Berk, a world-renowned ultra-modern research institution in its field, was located in a remote area where no one would ever want to go, just like every other world-renowned ultra-modern research institution: the isle of Berk. Where it snowed nine months of the year and hailed the other three. He'd eventually get used to it. He was a month into his semester-long masters placement, which meant he hoped to stay around for his PhD. Three more years of freezing to death. Pure bliss to look forwards to.

He shrugged it off and pulled the hood of the thick winter coat he was wearing beneath his lab coat back onto his head and resumed his pipetting. After weeks of doing essentially only that, Hiccup was getting seriously good at it. Within seconds, the last precise volume of solution had been poured out into his small cylindrical plastic tube, and a messy pile of pointy pipette tips lived in the transparent waste bin like a miniature spiky yellow and blue dragon, threatening to brim over. Still holding his pipette in his gloved right hand, he ticked off the reagents on his list with a pen in his left. He then meticulously poured the medium into a series of Petri dishes and plated his cells onto the gels before securely taping the boxes close, eyeing at the clock on the pearly gray wall opposite him. With some luck, he'd have time to put his put his culture to the fridge and autoclave the day's garbage before catching his bus back to his flat on campus. If not, he'd have to walk. Well, only if he was lucky enough not to be caught in some episode of violent snow storm.

At that precise time, however, the grad student was readying himself to face a different form of frozen tempest. One that carried the thrice-accursed name of Jack Frost.

Jack Frost. The immense fridge in the lab upstairs - or at least, the silly nickname everyone in the lab had given to it. Rooms and rooms of frozen semi-obscurity, filled with aligned metal shelves that carried endless piles of nearly identical-looking Petri dishes labelled in seemingly meaningless lists of digits and acronyms. Decidedly adjusting his lab goggles onto his freckled nose, he headed out into the corridor, past the alignment of white ceramic-covered benches. At this time, most everyone had left the lab, since the people of Berk started and finished their days early. Only the lab technician, Gobber, could be heard stomping around and whistling some mirthful air in the corridor.

Tossing his left glove into the bin as he passed by, Hiccup pushed the heavy lab door open and headed towards the spiral staircase. Lightly panting as he reached the first floor, he practically ran to the giant fridge, as an effort to keep himself warm. Oh dear, how out of shape he was. He half-pushed, half-collapsed against the massive door. And ended up in total, icily cold darkness.

"How in the name of Thor am I going to find my way in here?" he thought aloud sarcastically.

"...just grep it already..."

What could grep possibly mean… wait what? Was there someone in this artificial blizzard talking to him? Well, judging by the tone of the voice, more like mindlessly sleep-talking, but still… Was he turning crazy? Was the long day of lab work clouding his mind? Or was working on neurons messing up his own brain, as some twisted punishment for trying to play God… Oh, there. Hiccup's hand had finally managed to find the light switch, and within a fraction of a second, everything suddenly became clear.

And nonsensical.

For between the familiar symmetric shelves stacked with labelled boxes was a boy sleeping on a chair with a laptop on his knees. A boy sleeping on a chair with a laptop on his knees.

More precisely, a large, black, angular and heavy-looking laptop. A rolling-spinning-adjustable dark blue desk chair. And a young man looking hardly older than Hiccup himself, his hair dyed silver gleaming eerily in the fridge's white light, mumbling incoherently in his slumber. Hiccup couldn't believe his eyes.

Come on, do something, he chided himself mentally. He couldn't leave the unknown boy freeze to his death in his sleep. While putting his boxes onto his group's dedicated shelf, he tried to control his own chattering teeth and to think of something sensible to do. As he hesitantly stepped towards the chair, he noticed the computer's low grumbling. He tentatively touched it and immediately removed his hand, burnt by the contact. The machine was overheating. Well, that possibly explained why its user was sitting in there, as well as how he could possibly be alive and sound asleep in such a cold environment. Anyway, Hiccup had to take him out. He grabbed the back of the chair and wheeled it towards the door. And almost dropped the bulky laptop, catching it in extremis with his gloved hand. Smearing any traces of toxic reagents that may still have been sticking to his gloves onto the screen, but he hoped that the computer's owner would never come to notice that. Even though he had grown to be competent with his hands when it came to lab work, Hiccup's coordination when it came to real-life situations - and just plain weird ones like this one - was rather disastrous. After a few more or less awkward trials, he somehow managed to to open the fridge door and get the chair, laptop and boy safely outside.

"... mmh… warm…" Hiccup could hear the other muttering right into his ear.

He took the computer off the boy's lap and precipitantly put it down on the closest lab bench, over the polystyrene container filled with crushed ice that someone had left with tiny plastic vials in it. Wow, that laptop was heavy. So heavy, in fact, that he had displaced the unconscious boy's weight off the chair while trying to move it. Such that the boy was now leaning onto him. And, most likely as a reflex not to fall, as far as Hiccup could tell as to those wicked feedback loops of motricity, cuddling onto the freckled boy's arm as if to never let go. The grad student had to pull back for their foreheads not to violently collide. His fresh ivory cheek pressed over the shoulder of his lab coat, the sensation of his white snowflake-thin hair brushing against Hiccup's temple not actually that displeasing. Even so, it was awkward. Incredibly awkward. Especially if the other started to drool onto his personal lab coat. No, he was not letting that happen. Never. Still trying not to wake him up, he gently pushed him back onto the chair, his left hand cupping up his chiselled jaw to make sure he didn't hit his head. His bare thumb delicately moved up his youthful chin as he rested his pale head against the back of the chair, lingering ever so slightly more than needed on the corner of the unknown boy's thin sculptural lips...

"... warm... mmm… nice … Wh - what the hell?"

Hiccup's freckled cheeks immediately blushed crimson as he precipitantly stepped away from the chair. He tripped on one of those treacherous lab stools behind him and nearly lost his balance. The silver-haired youth looked surprised, but not shocked or panicked. His eyelids quickly fluttered, dispelling the last remnants of his dream. His sky blue irises stared straight into Hiccup's eyes, provoking a strange shiver down his spine. He forced himself to breathe in deeply to calm the thundering thumps of his heart.

"I'm sorry, I didn't… I… what were you doing all alone in the fridge? Melting the ice with that burning hot... erm... thing of yours?"

Hiccup vaguely waved towards the computer sitting on the table, unsure what to call it since it was the most not-portable 'portable' computer he had seen in his whole life. Unsure, in fact, that he meant the burning machine or… to something else that was hot about… him? His tiredness was definitely starting to mess his thoughts up. The entropy was getting seriously high at that time of the day.

"Laptop overheating. Had to cool it down," he answered while briefly checking up on his computer, typing at what seemed to Hiccup as record speed.

And even that guy's voice sounded as cool and collected as that of an angel, fallen straight from the snowy clouds. Not at all like someone who had been caught red-handed napping without even safety gloves in a lab-gear-only area. Hiccup, meanwhile, was a heap of reddened awkwardness, wishing he could discreetly melt into the floor. Such a great start to setting up a cordial colleague-to-colleague relationship with someone whose company he'd probably have to endure in the next few months, if not the next three years of his PhD… Great networking skills, Hiccup, he chided himself. Sure, that looked so confident and professional.

If the grad student hadn't been so focused on trying not to hyperventilate, he'd probably have noticed the other's cerulean eyes checking out some of the more... interesting folds of his lab coat.

"But why were you in there?" the brunette somehow managed to stammer.

"My laptop lives where I live. They haven't given me a proper machine yet, that one is all I have. Just arrived here a couple of days back."

"And… why were you… erm… sleeping in there? You know… Gobber… if he found you… would have kicked your arse… wait, no, sorry, I didn't mean… I'm so sorry, I… um... I mean… your arse is-"

Just when he thought there was no way it could get more embarrassing. That was all great. A gentle blush dusted the pale young man's porcelain cheeks, which definitely didn't help.

"Post coding-marathon nap. And jet lag. Oh and… your arse isn't that bad either, by the way."

The typing went on more furiously, the man's hands seemingly moving automatically while his eyes were hardly taken off Hiccup's face. The brunette student brushed the back of his head in utter embarrassment, eyes darting around vividly for any source of escape. By incredible chance, as if, for once, all the black holes and quantum waves of the universe had decided to collapse and align his way, deforming the very fabric of spacetime in that deed - for, as a rigorous scientist, he refused to refer to destiny or any other form of stars randomly looking a bit closer to each other - the time displayed in the bottom corner of the huge laptop seemed to answer his desperate prayer.

"Erm… my… I…late... my bus… gotta go… um… nicemeetingyouhaveaniceevening!"

Before the programmer had time to react, his interlocutor had already dashed out of the room in profusely blushing precipitation. All he could see of him was the flapping stark white tail of a lab coat, with the schematic doodle of a fishbone in black marker on his back.

"Wait- "

He hadn't even had time to ask for his name.

Or to thank him for saving his butt.

Or to buy him a coffee as a thank-you.

(For even though he had spent little time working with academics, even he was not unaware to the universal truth that no one in a research lab would ever turn down a coffee.)

His eyes fell back onto the chaos of aligned white figures and letters that poured out onto the black window of his terminal. His brain was a mess, his hair was a mess - but he knew it looked better that way, so he hardly minded that part - his code was a mess… The entropy of the universe was definitely reaching skyrocketing levels.

"Why do I make such a mess out of everything?"

The mind, meanwhile, had many messy ways of working of its own and a funny habit never to clearly and understandably signal to its owner, such that he hardly knew where that fuzzy feeling of fresh fluttering snowflakes at the bottom of his stomach had come from.

EDIT (08/02/2016): Previously forgot disclaimer, my bad. I DO NOT OWN RISE OF THE GUARDIANS OR HOW TO TRAIN YOUR DRAGON. These belong to William Joyce, Cressida Cowell and Dreamworks.

Cover art done by me, full size version available on my DeviantArt under the same name (eliazeravenfeather)

Don't worry, the next chapters are planned to be much longer (makes up for the really long chapter I posted less than one day ago for my ongoing fic, I guess. Which you should check out, by the way - winkwink).

As you might have seen me announce elsewhere, this is some kind of modern AU set in an academic lab, which may alternatively be labelled College AU or Nerd AU… Berk is supposed to be located somewhere like Northern Europe, which is why people go to work so early and leave so early - save for Hiccup since he's probably been studying abroad for a bit, and Jack because he's American and because he's a mess.

Just so you know, the title refers to the Butterfly Effect - by which small causes may randomly have large effects - and the Snowball Effect - by which a small phenomenon builds upon itself to become something of much greater amplitude, for better or for worse. I know, I'm terrible at titles.

As a general warning: things are going to get fluffy (even more). And angsty. And geeky.

R&R, F&F, say awesome xx