Harry sat at the window and smiled as laughing students scrambled into carriages, eager to be home for the holidays. The last few days of term had been filled with hysteria in anticipation for the Christmas break; first years running and screaming through the corridors, people humming Christmas carols at irregular intervals and general light-heartedness that was generated by the season of goodwill.

Harry had watched all of this, enjoying seeing everyone in such high spirits, but had not participated. Naturally, after the defeat of Voldemort last spring, people were even more exuberant than usual regarding Christmastime – everyone seemed to want to go somewhere or do something special to commemorate their first Christmas free from the Dark threat. Even the Weasleys had decided to go to Majorca to celebrate the freedom. Mrs Weasley had actually gone so far as to extend an invitation to Harry and Hermione, but they, knowing the Weasleys’ budget was already drawn tight by the whole family going abroad together, had declined.

Hermione had quite happily said she’d stay over the break to keep Harry company in the empty Gryffindor Tower, but at the last minute, disaster had struck. Hermione’s grandmother had died quite suddenly, leaving her whole family in shock. And so Hermione, in floods of tears, had told Harry she couldn’t stay after all. Harry had given her a hug and told her that he quite understood, and so, with another hug from Harry and some awkward pats from Ron, she had calmed down and gone upstairs to pack.

And here Harry was, sitting on a windowsill directly above the Main Entrance, watching his year-mates and the younger students pile into carriages in preparation for the trip home. As far as he’d heard, only a few other war-orphans were staying at Hogwarts, and none of them were in Gryffindor, let alone in Harry’s year. Harry settled his head against the freezing glass and waved as Ron and Hermione looked back for one last time before climbing their into the carriage.

And then they were gone.

Harry sighed, climbed off the window ledge and trudged towards the library, trying not to think how lonely it would now be. His friends had promised to write every day; well Hermione would write every day, Ron would just write letters filled with apologies whenever he remembered. It was a strangely comforting thought.

Now, normally Harry would have been heading towards the Owlery to chat to Hedwig while trying to forget what the coming Christmas would be like, but this year Harry had something better to do. As soon as he’d heard that Hermione would be away as well, he had filled his days with things to do, which would leave him no time to think about anything else. In fact, Harry had already completed all of his holiday homework.

Hermione had been very impressed.

And so, trying to find an activity that would completely consume all his time over the holidays, Harry had stumbled on the perfect answer. Entering the silent library, Harry snuck over to the Restricted Section and placed his wand to the lock, murmuring the charm that would permit any seventh year to enter. Not for the first time, Harry blessed his newfound privileges.

Confidently, he walked between the shelves and pulled down a well-thumbed book, spelling an illusion of it in its place. Silently, Harry crept out of the library once more, the book stuffed under his shirt. He only had to check a couple of things from it, and in just a few more days, he would be ready.

~~~~~~~

Harry pushed his glasses up his nose and took a deep breath. This was it. The moment he had been anticipating, dreading, and waiting for ever since he had discovered the book. He took a quick peek up and down the corridor before taking out his wand and placing it against his chest. He had chosen a public corridor just outside the Headmaster’s office in case anything went wrong his first time. He didn’t want to spend hours alone up in the Gryffindor dorms, waiting for someone to come and help him if he had an accident with the spell.

He looked down in surprise to see his hands shaking. “Come on, Harry,” he muttered softly. “You only need the spell for this one time and you know the incantation off by heart…” Taking a huge breath, he tucked his wand inside his shirt, next to his heart, and started chanting in Latin.

Deeper and deeper he pulled himself into the trance, letting the words and magic guide him, feeling them both ebb and flow within his very soul. Spitting out the last phrase, which sounded much harsher and more sibilant than the rest, Harry curled up into a ball and waited.

One second…

Two seconds…

Thr…

Harry gasped as something seemed to squeeze his heart. Steel bands contracted around his chest and he felt like he was being turned inside out, upside down and whirled around simultaneously. There was no time to catch a breath, just a crazy spinning that left Harry feeling vaguely nauseous and madly dizzy, and all within the space of about twelve seconds.

Harry gasped a breath the second he could and flopped, panting, onto the soft window seat while waiting for the dizziness to abate. His body felt different, strange and at the same time, achingly familiar.

He had done it.

He had become an Animagus.

But then why did he feel so cold? So very, very cold? And why was the world dimming, becoming further and further away with each shaky breath? Cold…

Harry Potter, the Boy-Who-Lived-To-Destroy-The-Dark-Lord lost consciousness, his little body going limp and collapsing onto the windowsill.

~~~~~~~

Severus strode sedately along the corridor, enjoying the bliss that was the most complete silence in Hogwarts for the first time in months. Doubtless, within a mere three days, the quiet would begin to grate on his nerves, but for the moment, he could enjoy the new stillness that had settled over the castle.

Approaching the corridor that led to the Headmaster’s office, he was startled as a low hiss broke the silence. Despite having been made redundant from his spying position by the joyful demise of his former Master, Severus had lived most of his life being cautious and was unwilling to give up the habit just yet.

Pulling his wand out, he crept around the corridor and looked around.

Nobody there.

However, on his second inspection of the hallway, Severus realised that there was something there after all.

Draped across the nearest window ledge, unconscious and barely breathing, was a young snake. Severus stepped closer, intrigued. As a rule, snakes were forbidden as familiars at Hogwarts; mostly because the more ‘interesting’ varieties ended up putting several people in the Hospital Wing with poison-related maladies. However, every now and then, someone would try to sneak one in, regardless of the rules.

Severus sneered in disgust. The student who had smuggled this poor creature in had obviously discovered how much hassle it was to look after a snake, and had abandoned it the first chance they got. The miscreant responsible ought to be strung up by their thumbs in the Entrance Hall. It was Severus’ strong opinion that if a person couldn’t take care of their familiar, they should never have got it in the first place.

Ever so gently, Severus reached out and picked up the little creature, handling it gently so as not to harm it. It was freezing.

He quickly cradled the creature closer to his body so that it could share his heat. It was only about twenty four inches long, but Severus knew most snakes did not stay this convenient size, which was one of the main reasons for their abandonment. He turned the dun-coloured creature over in his hands and gasped when he realised what species it was. He hurriedly grabbed his wand and cast a spell that would prevent the creature from opening its mouth too wide if it chose that moment to wake up.

It was a Spectacled Cobra – or Indian Cobra according to some people – and was considered one of the four most venomous snakes in India. Severus had no desire to require an antivenin so soon after finding the creature. Thank goodness it had been unconscious when he’d come across it!

Severus hurried towards the dungeons, still worried about how cold the creature had gotten. Whoever had abandoned it should be put up on charges for animal cruelty. Reaching his quarters, he conjured a flat stone and set it in front of the lighted fire, casting a strong heating charm on it as he went. He then gently placed the snake on it, conjuring a bowl of water to go next to the rock in case the snake was dehydrated when it woke.

The next question he needed answered was if it were considered a ‘magical’ pet, or a normal one. The ‘magical’ ones were snakes that had evolved around wizards, meaning that some of the magic had been absorbed into their systems, enabling them to understand most human speech without that human being a Parselmouth. Casting the spell, Severus sighed in relief as the diagnostic indicated that the snake had strong traces of magic around it. At least this snake would be easier to handle than its ‘Muggle’ cousin.

Severus settled behind his desk and began to grade the papers that had been handed in the last lesson of term. In a fit of festive cheer, to which not even he had been immune this year, he had taken an inch off the traditional four foot essay he gave the students at the end of term. He smirked, idly twirling his quill between his fingers. That hadn’t stopped them from grumbling, though.

Every five minutes, Severus found his head snapping up to check on the snake. It still hadn’t woken up, but gradually, as it got warmer, the creature curled in on itself until it was resting in a more natural position.

Finally, while Severus was debating over whether or not to take a mark off for bad grammar on a salient point, he heard a soft splash. Blinking, he looked up in surprise at the cobra which was now greedily gulping the water. The poor creature must have been in terrible state. Unable to concentrate on the essays anymore, Severus got up and slowly approached the snake, carefully settling on the ground five feet from its resting place.

The snake finished drinking and slowly raised his body to gift Severus with an unblinking stare. Well of course it wouldn’t blink; Severus thought to himself, it’s a snake! He decided to see if he could break the tension between them; the creature might be magically gagged at that moment, but it was still one of the most poisonous snakes in existence and Severus didn’t want to get on its bad side.

“Hello. I see you’ve finally decided to join me.”

The cobra’s hood flared a little and the snake didn’t break eye contact.

“I discovered you unconscious on the seventh floor, no doubt where you were abandoned by your owner, and I brought you down to my dungeons. I trust you are more comfortable now?”

The snake’s head dipped slightly, before the little creature started hissing in agitation, swaying its head from side to side.

“I am afraid I cannot understand you. I am no Parselmouth.”

The snake uncoiled itself and slid onto the floor, wincing as the warmth of its stone was replaced by the distinct chill of the dungeon floor. Severus quickly remedied the situation with a flick of his wand and felt the floor heat beneath him. The snake’s next hiss was almost a purr.

It slowly slid up and onto the Professor’s lap, hissing softly and looking up beseechingly. Before that day, Severus didn’t even know that snakes could look beseeching. Severus had tensed when he felt the first coils settling on him, but now he relaxed. The snake obviously meant him no harm, and by the look of it, it obviously wanted his help with something.

“What is it? Are you hungry?”

The snake looked frustrated for a moment – unfurling its hood and swaying a little once more – before it looked at Severus again and dipped its head gracefully.

“Accio Mouse! Stupefy!” A little, grey object flew across the room and stilled.

The snake hissed in irritation as its prey stopped moving and sent a very effective glare in Severus’ direction.

“I have to take the charm off that’s preventing your jaws from opening properly. Otherwise, you wouldn’t be able to eat the mouse, whether it was moving or not! Now, promise not to bite me and I’ll take the spell off.”

~~~~~~~

Harry eyed the wand in Snape’s hand and dipped his head. He was hungry, and for some reason he didn’t want to consider too much, he really wanted to eat that mouse. It had taken him a while after his return to consciousness to work out which animal he had become, but once he started the hissing and the slithering, it was pretty easy for him to guess. Also, there were some flaps of skin by his neck which hinted that he may be some kind of cobra. Harry was really pleased by this; after pythons, cobras had always been his favourite kind of snake.

He had wanted to be something warm-blooded like his father and the Marauders, but he could see the benefits in this form as well, and did not mind too much. Unfortunately, his most pressing concern at that moment was that he could not find a way to change back.

Foolishly, he had got lost in the last line of the spell, due to the sibilance and its similarities to Parseltongue, and he had accidently changed one of the words. Nothing too pressing, all it meant was that before he could resume his human form, someone had to cast the spell that would reveal him as an Animagus. After that, he would have no trouble with changing back and forth between forms.

Unfortunately, this now meant that he had to convince someone that he was an Animagus; a difficult task in itself, with the annoying side effect that he would lose the brief anonymity that an animal form might have given him.

To make matters worse, Snape had found him. True, their rivalry wasn’t as bitter as it had been before the death of Voldemort, but it was still present. He shuddered to think what Snape what do to him once he found out the truth.

Strangely, Harry found he didn’t mind the mocking as much as when he was younger – these days he could see that he deserved it, and at least Snape no longer made references to his father. Harry knew without a doubt that on this occasion he most definitely deserved Snape’s derision.

The tingling around his jaws made Harry pause in his thoughts and look back at the mouse just as Snape whispered ‘Enervate.’

Harry looked down at the little creature with a strange thrill running through his belly, and hissed. The mouse jumped and shot off at top speed, but it was too slow for Harry. Quick as a flash, he snatched the creature and bit, savouring the feel of his razor sharp fangs sinking into flesh and the taste of the venom being injected into his prey. Part of Harry knew that he would be terribly disgusted by this once he returned to human form, but his snake mind didn’t care.

With a click of the jaw and a few swift gulps, the mouse disappeared. Harry looked towards Snape smugly, and the man rolled his eyes. Harry snickered sibilantly and slithered back to the man, sliding smoothly underneath one of the large hands.

“Yes, yes, you are the expert killing machine etcetera, etcetera and I am amazed by your singular skill. Now would you mind going back to sleep while I go and mark the incompetent children’s essays?”

Harry snickered again and let himself be set back on his rock. He was feeling sleepy after his latest meal anyway and his snake instincts told him relax and digest the latest morsel a little before trying anything else. Letting Snape know that he had been kind to his least favourite student could wait.

~~~~~~~

Harry stirred and woke once more to the wonderful warm feeling that made his blood feel alive and kept his spirits high. He was faced with two options; stay here and bask in these superb feelings, or go and find Snape. Feeling curious, he lifted his head and was surprised to see Snape still at his desk, despite the large clock on the wall saying that it was eleven at night. Had anyone missed Harry Potter yet? Or did they simply think he was moping and missing his friends?

Harry sighed a snake sigh and slithered towards the desk. It was difficult to feel sad for long with the wonderful heat seeping through the stone and warming his scales. Harry stopped at the foot of Snape’s chair and looked up. The man was bent over the parchment on the top of the desk, softly snarling under his breath. Harry decided that he wanted to see.

He curled his versatile body around Snape’s booted foot and lazily spiralled up the leg. Harry was gratified when the leg went tense and the man froze; he was a dangerous snake after all, people should fear him! Unfortunately, it also had the side effect of making him want to sink his fangs into the calf laid temptingly in front of him. Harry had to berate himself several times that it was not a good idea to poison the Potions Master – he was the one who poisoned other people! In ways, the man before him was the king snake of them all and it would not do to anger him.

Reaching the desk, Harry slithered up and on and hissed his amusement to the shaken man. He got a wand pointed in his face for his troubles.

“Don’t you ever do that again, you infernal creature!” Snape looked pretty angry, but Harry knew the man wouldn’t hurt him. Nonchalantly, he flickered his forked tongue over the end of the wand and turned to see which essay had Snape so upset. He heard the man behind him sigh and mutter something about ‘bothersome serpents’ but paid him no heed.

The essay really was abysmal. Even Harry could have written better in third year. He hissed in disgust and shook his head. Snape snorted and gently touched a finger to the snake’s head. Harry leaned into the touch.

“It’s nice to see that you at least have good taste, my friend.”

The endearment brought Harry up short. He thinks I’m a snake! He might even be getting attached to me… Harry felt surprisingly sad at this thought, imagining himself finding a new familiar, only to discover that it was someone he truly disliked in Animagus form. He snapped his head about, searching for inspiration to reveal the truth, and struck gold.

The red inkpot was sitting right in front of him. Harry brought his tail around, balancing carefully, and somehow managed to dab the tip into the bottle. Snape snorted and tried to push the glass object out of the way, but Harry hissed at him so fiercely that he immediately snatched his hand away. Harry moved his tail over to the parchment and tried to scratch letters on it.

After five minutes of fruitless attempts, and a new piece of parchment provided by Snape, Harry had a brainwave. His tail was flexible, but obviously not flexible enough for something like letters. However, it might work for something like symbols!

Looking up at Snape, who had his head rested on one hand while idly watching the snake, he hissed and dipped his tail once more into the inkpot. Snape glanced down at the new symbol the snake had drawn and started, turning to stare at Harry with wide eyes.

Harry repeated the symbol again, and again; over and over, until the little red lightning bolt decorated almost the entire page. The look in Snape’s eyes changed slowly from astonishment to comprehension. Harry knew the man would get it in the end; he was very bright, after all.

Snape’s eyes narrowed dangerously and Harry gazed back calmly as the thin lips curled distastefully around one word.

“Potter!”

~~~~~~~

Severus watched the snake lift its gaze to the ceiling as if to say ‘Finally!’ before it looked him in the eye and dipped his head. Surprisingly, the creature didn’t look afraid, simply curious, but Severus was too angry to think about that too carefully.

“Get over here at once, you troublesome brat!” Severus held his hand out to the creature and beckoned impatiently. Even in his anger, he wasn’t foolish enough to grab an extremely poisonous snake.

The snake slid over his fingers and coiled around his arm. He refused to think of it as Potter, not yet. For a start, the boy would not be nearly so calm around him.

He carefully placed the snake in the middle of the floor, far away from any furniture, and took a step back. “What in Merlin’s name were you thinking? The Animagus Transformation has claimed more lives to date than any other spell save the Unforgivables! You imbecilic child! You just had to go looking for trouble, didn’t you? What if you had transformed into an aquatic creature? What then? I’ll tell you; you would have been a lot worse off than simply being unconscious from the lack of heat! As it was, you could have died from the chill if I hadn’t been passing by!”

Severus sighed and pinched the bridge of his nose, feeling marginally better for venting his spleen when the boy couldn’t use that annoying habit of his of answering back. He chanced a look at the cobra, which had the good grace to look ashamed.

“Animagus revelio!”

A blue-white flash of light enveloped the snake’s form, sinking into its skin, and the next second the creature twisted and grew rapidly into the crouched form of Harry Potter. The boy’s wand clattered to the floor and he groaned, rubbing his back as he stood and stretched.

“Mr Potter…”

“Yes, yes, I know I was an idiot and there was no excuse for me to try something so stupid. Just bear your lecture in mind for a minute, I have to try something.” The boy’s green eyes flicked up to his teacher’s face. “I would feel a lot better trying this while you’re still here watching me.”

Severus’ eyes narrowed, but he said nothing. Potter took this as consent and grinned, placing his wand carefully on a nearby chair. Severus’ expression didn’t change once as the boy quickly shrunk into the form of the familiar snake before re-growing into Harry Potter.

“Excellent!” The boy beamed to himself, and he looked towards Severus as he gathered up his wand. “You were saying, Professor?”

Severus glowered. This boy was not the annoying, little monster who had been haunting his classroom for the past seven years, nor was he the quiet, thoughtful boy that had emerged after the Dark Lord’s defeat. The Animagus Transformation had given the young man standing before him a confidence that not even Severus at his most vitriolic could dent. Severus had seen it before with the boy’s father and his cronies, though at the time he had not known what had caused it.

“By tomorrow, I expect to have heard that you went straight to the Headmaster and were consequently registered at the Ministry as a matter of course. Regardless to say, if you try any more stupid stunts you pull while you are still at this school, you will find yourself extremely sorry! Now, get out of my rooms and stop spoiling my holiday!”

Potter blinked and cocked his head like his snake-self would have done when puzzled. Severus could almost see the cobra’s hood raising at his neck.

“You’re letting me go? Just like that?”

“Needless to say, after you saved the entirety of the Wizarding World last spring, there is no point in me even trying to get you expelled. Now, get out, I have essays to mark!”

Severus whirled around impressively, grateful that he wore his teaching robes even in the privacy of his own rooms, and stalked to his desk. He heard the door snick open, but not the soft click that would have occurred if Potter had shut the door. After a moment, he glanced around.

Potter was standing in the doorway with an odd expression on his face; something between bemusement and humour. “Thank you, Professor.” The door shut with a soft click and Potter was gone, leaving Severus staring at the heated stone and bowl of water still in place next to his hearth.

~~~~~~~

On the morning of Christmas day, Harry opened his eyes and quickly sat up and reached for his presents, grabbing his glasses as he went. He had more than ever this year, but that was mostly to do with the little tokens people kept sending him as thanks for saving the Wizarding World. He idly wondered if people would ever listen to him when he explained that he hadn’t done it all by himself…

Probably not.

He quickly sorted through the ones which looked like presents from his fans – distinguished by the purple and gold hearts sprinkled all over the paper – and pulled out the authentic ones.

He got the traditional Weasley jumper and a letter from Molly Weasley in which the first page admonished him about even attempting something as dangerous as the Animagus Transformation, and the second page congratulated him on the same thing.

Harry’s friends had really forked out this year; Ron had given him a watch, which Harry immediately loved even though it was a bit battered, and Hermione, bless her heart, had bought him a mobile phone, which he couldn’t wait to try out once he got on the outside of Hogwarts’ disastrous influence on technology.

Everyone else had given him the usual hotchpotch of miscellany, sweets and home-cooking. For some reason, Dumbledore had given him a funny book on how to knit socks. Maybe the old man was hinting at something…

Harry leafed through the book, laughing happily at some of the articles he found before turning to his last gift on the ‘genuine’ pile. It was wrapped in brown paper and Harry couldn’t imagine who it was from, for he had opened all the presents from the people he normally received gifts from. Carefully, he peeled of the paper, keeping his wand handy in case in was cursed; after all, the war hadn’t even been over for one year.

Harry pulled the last piece of wrapping away and stared at the thing in his lap. After a second, he broke into a huge grin. There, surrounded by brown paper was a magically heated stone and a shallow water dish, accompanied by the terse note; ‘Potter, from now on, you might be needing these.’

Harry smiled happily and ran his hand over the warm smoothness of the stone. He could only hope that Snape liked Harry’s Christmas present as much as Harry liked Snape’s.

~~~~~~~

Down in the dungeons, Severus poked suspiciously at the unlabelled package once again. He had many enemies and there were many more people held a grudge against him. Normally the House Elves rooted out the malicious ‘presents’, which made the appearance of this one even more mysterious. The large package was tastefully wrapped in black paper and tied with a silver ribbon. It was this fact alone which had prevented him from disposing of it the moment he saw it.

In the end, curiosity won over and Severus gingerly unwrapped the thing, using his wand only. Inside was what looked like a glass tank filled with lots of rocks. Baffled, Severus walked around it once, trying to work out what it was used for. Normally he would have thought Albus would have given it to him purely for comic relief, but the Headmaster had already given him an old grimoire that Severus had been hankering after for a while…

Leaning closer to the thing, he noticed that there was a slip of paper stuffed between two rocks. Reaching into the tank, he gently teased it out and unfolded the parchment once it was in his hand. His eyebrows rose as he recognised the familiar scrawl.

‘Dear Professor, I hope you will accept this terrarium; after all, you never know when you might need to house a wayward snake. A Merry Christmas to you from the bane of your teaching career.’

A soft snort echoed through the dungeons, closely followed by another, louder one. Unable to help himself, Severus Snape doubled over at the waist, clutched the edge of the tank and laughed so hard that his stomach ached. Of all the nerve!

~~~~~~~

Harry hurried outside into the huge drifts of fluffy, white snow. He had every intention of building a snowman before Christmas lunch and nothing, not the freezing cold air, nor the inherent childishness of the action, would stop him. He was seventeen and a qualified Animagus, not to mention a hero of the Wizarding World; he could do whatever he liked! Though, he would have to cast a warming charm before he started.

His Animagus form had made him very sensitive to temperatures. In fact, the quandary of what to do with himself over the holidays had been solved by the simple activity of basking for hours in front of the roaring fire in the Common Room. Harry dreaded to think what would happen when school started again and he would have assignments to complete.

His warming charm in place, Harry balled up as much snow as he could and rolled it along the ground so that it could gather up more. Suddenly spying a figure striding around the edge of the frozen lake, Harry changed his plan.

With a smirk, Harry levitated the now heavy ball and cast a mild Banishing Charm on it before nonchalantly turning his back and starting the process of making his snowman once more. A few seconds later he heard a loud cry and a muffled thump. Harry started cheerfully whistling ‘Deck the Halls’ as he continued rolling his large ball of packed snow along the ground.

A couple of minutes later, a large shadow fell over him and his masterpiece-in-progress. “Mr Potter.”

He looked around. “Oh, hello, Professor. Did you like your Christmas present?” Harry had a very hard time keeping his face straight. Snape was almost completely covered in snow; clumps in his hair, on his woollen robes and encrusted to his boots made his apparel look more white than black.

Not surprisingly, Snape did not answer his question.

“I do believe that you are responsible for my current condition, Mr Potter,” he said while emphatically brushing a small amount of snow off his shoulder.

Harry looked up at him with big, innocent eyes. “Why, Professor, I have absolutely no idea what you are talking about!”

In answer to this, Snape slowly pulled his wand from his sleeve and gave it a decisive flick. Before Harry could even think to run, a huge mound of snow lifted into the air and dumped itself over his head, burying him completely. Harry’s warming charm was rendered completely useless.

Floundering a little under the mountain of white, Harry broke through the top and shivered violently, looking at Snape with beseeching eyes. “C-c-c-cold.”

Snape smirked.

“Well, look at this! I seem to have found myself a wayward snake. Luckily, I have just the place to put it. Come along, Potter.”

Snape grabbed Harry’s arm and tugged him out of the snow drift. Harry transformed and wrapped himself around Snape’s arm, his scales briefly shuddering with the cold.

Snape pulled the creature close to his chest, letting his body warmth leach into the small snake as walked back to the castle. And once again, Harry allowed himself to believe that impossible things could happen after all.