A/N: Written for the Timepetalsprompts weekly ficlet theme - Back in time. It's a Hogwarts AU. Or a crossover? I always get confused when it can be counted as a crossover. Unbetad, so all the mistakes are mine.

"What do you think?"

"I think he's definitely not telling us something!"

"Yeah, he keeps disappearing. It's like magic…"

The three girls giggled and ducked behind the Muggle Studies shelf in the library. They looked something like a girl band - the blond, the brunette and the ginger standing in a row, wearing the same uniforms.

"Where's Martha?" the blond one asked.

"Studying, as usual, I'd expect," replied the ginger and scrunched up her nose.

"Just because you think you can get by with me doing all your homework doesn't mean everybody else can skip studying too!" retorted the brunette.

"Hush, Clara, Professor Longbottom is coming!" the blond one tugged on the sleeves of the other two and they ducked behind another set of shelves, inching closer and closer to the Restricted Section.

"Amy, get off my foot!" hissed Clara.

"I'm not standing on your foot!"

"Yes, you are… Wait! Ew. Whose toad is this? Rose!"

The blond burst out laughing and clutched at the shelf to keep herself upright as her friend tried to get the toad away from her shoes. It held on for dear life and nothing could shake it off.

"Come on! Amy, help!"

But the other girl was too busy laughing as well.

Clara was about to take out her wand and make the animal get off by force when a boy in black and yellow uniform came sprinting around the corner.

"Have you seen my… Oh. Sorry about that. She's just a bit queasy after the train ride," he apologized to Clara and hurried to get the toad off her.

"Train ride? Rory, it's the middle of October! Where have you been?" Clara asked, annoyed.

"Um… my mom…" he picked up the toad and dusted her off, looking anywhere but at them, "she got sick… So I had to go home for the weekend…" he trailed off, looking so miserable that Clara immediately felt awful for snapping at him.

"Oh. I'm sorry," she replied flatly, glancing at Amy, trying to urge the other girl to do something. Amy just rolled her eyes and walked over to Rory, putting her arms around his shoulder.

"You okay?"

He looked up briefly at her and managed a smile when she nudged his face with her nose. "Yeah. Great! I'm great. She's doing better, but they don't know what's wrong with her, so… we don't know what's going to happen."

"I'm sure she's going to be fine," Rose squeezed his hand, "the Healers at St Mungo's are great, they're going to find out what's wrong."

He nodded again and put his toad into the pocket of his robes.

"So, what are you all doing, hiding behind a bookshelf? Again," he added with a look that left no doubt to any passers-by what his thoughts were on the matter.

"We're trying to find out what Nathan is up to," piped up Clara excitedly.

"Has he been disappearing again?" Rory asked.

"Yup. He's always babbling on about homework and whatnot, but we checked and he's not in the library," Rose motioned around as if to say we've clearly looked everywhere.

"Well, have you checked the…"

"Common room?" Amy finished for him. "Yes, we did, stupid face. That was our first stop. He's not there. He's not in the boys' dormitories either. We know, Jack told us."

"Okay, so where is he?"

"We don't know. Trying to find out," Rose nodded significantly. "We might have a lead, if only we can find Hannah. She said she has some idea about the topic, but she was running out of the room by the time I woke up and hadn't told me what that idea might be."

"Well, then all we have to do is find her," Amy tussled Rory's hair who flinched, but let her.

"Yeah, like that's gonna be hard," snorted Clara. "I bet she's snogging his boyfriend senseless in some shadowy corridor on the Seventh Floor."

"Wouldn't be out of character…" mumbled Rose.

As if on cue, they heard muffled giggling from the row right behind them. Removing a few books from the shelf at eye level revealed Rose's sister in a state of semi-undress, with her boyfriend, Aiden leaning her against a shelf and kissing his way down her neck.

The three girls and Rory grimaced and heaved a sigh, walking over to the pair still deeply involved in shoving their tongues down each other's throat.

"Sister dearest, if you could stop for a minute…" Rose knocked on the books beside her ear, but Hannah simply batted her hand away.

"Seriously, why do they have to do it in the library? Madame Pince could come any minute and throw us all out!" Clara complained.

"Well, as good a place as any," Amy supplied. Rose and Clara shared a look when Rory blushed, and shook their heads. Rory and Amy have been in love practically since they met, but both were too thick to see it. Now, five years later there really wasn't much patience left in their friends.

"I bet Rory would not disagree…" mumbled Rose under her breath, then pulled on Aiden's green tie to separate him from her sister.

"Ouch. Hey, Rose, that's not…"

She smiled sweetly at him and he grimaced, loosening his tie further then taking it off completely.

"Alright, what do you want?" he sighed.

"Nothing with you, thanks," Rose replied. "I want a word with my sister."

Hannah smiled sweetly at Aiden and shook her head at Rose. "Alright, little sis, what is it?"

Hannah and Rose loved each other, despite their constant bickering, but they couldn't always communicate properly. Being twins, they've been together since birth (with Hannah being the eldest and using every opportunity to rub it under Rose's nose), and they have bickered for nearly as long. Even though their appearance was much the same - although they were very careful to dress differently since the age of seven and to never have the same hairstyle - their personality was as different as it could get. Rose was a Gryffindor, for a start, while Hannah got sorted into Slytherin. Hannah was the typical girly girl, always wearing her skirt shorter than the intended length, her hair falling in perfect curls down her back and around her shoulders, changing boyfriends like other girls changed clothes since third year. She started dating with her best friend, Ben, at the end of last year, but it didn't go well. No one knew what happened exactly, Hannah wouldn't even tell Rose, but they never talked anymore and Hannah was single for three whole months during the summer break. Which worried Rose more than when she said she wanted to go on exchange to Castelobruxo and become a Magizoologist. But then Aiden came along - a new student from Beauxbatons who apparently arrived at the beginning of the year - and Hannah seemed to gain back some of her vitality. Or maybe too much of it, thought Rose as she reached out and buttoned up the rest of her sister's shirt.

"It's about Nathan. You said you had some idea about where he disappears to."

"And why do you want to know so bad, hm, Rosalinda?"

Rose scowled and was about to start arguing when she realized Hannah was baiting her. The mischievous tinkle in her sister's eyes told her she didn't mean any of the teasing, but still enjoyed it immensely.

"Cause! I wanna. What's it to you?" she replied gruffly.

Hannah looked over to Amy and Clara who both cleared their throats and tried hard not to grin.

"What?"

Her friends smiled on and Rose started to feel her cheeks burning.

"I just want to know because I'm worried about him!" she blurted out.

"Aha. And it would have nothing to do with the fact that you fancy him, now would it?" teased Hannah mercilessly.

"Fancy him? What are you talking about? We're just friends," Rose spluttered.

"Yeah, right, friends. If you take my advice sweetheart - friends don't look at each other that way. You should make a move, he fancies you too. He's just too shy to ask you out himself. You gotta have to take the first step if you want this to work."

"I'm sure he doesn't fancy me, Hannah. He would have told me by now. Always says I'm just a little ape anyway," Rose muttered. She wasn't quiet enough though, her sister heard.

"No, he always says you're his stupid ape, Rose. There's a difference. Besides, why do you think he didn't come to the Yule Ball? He most probably had no one to go with."

"That's not fair! I don't understand why he wouldn't have! If the other girls don't realize what a catch he is, they simply don't deserve him." Rose stood stock still after her outburst and closed her eyes against her friends' loud laughter.

"You're going to have to admit you fancy him, Rose," Aiden interjected.

"Yeah? And who invited you into the discussion?" Rose spun on him and jabbed her index finger into his chest. She didn't like him much - was too afraid he'd break her sisters heart, although she'd never admit it out loud.

"Ouch. Calm down. Nothing wrong with fancying Nathan! Well, apart from his ears…"

"There's nothing wrong with his ears! Not everyone has to be a pretty boy like you, Mister Hoynes."

He laughed and gave her a charming smile that made Hannah grin, but only served to make Rose roll her eyes.

"What's wrong with being pretty?" Rory asked and Amy burst out laughing.

"Nothing. Our Rose just happens to prefer…" Clara bit her lip and watched as Rose turned a bright shade of red, a vein becoming clearly visible on her neck.

"Fine! If all you want to do today is to mock me, I'm gonna go and find him on my own! I don't need you lot to make fun of him behind his back!" And with that she stormed off, knocking into people, not looking where she was going.

"That might have been a bit too far," cringed Clara.

"She'll get over it," shrugged Amy.

"You should try the Seventh Floor!" Hannah shouted after her.

Rose didn't react, just hurried on faster than before, face still red, her honey-brown eyes spitting fire. A few first years stumbled out of her way as she stomped towards the Grand Staircase. She was still fuming when she arrived on the Seventh Floor, not quite sure when she decided to take Hannah's advice in going there, but given that she already climbed up this high, she wasn't going to go back. She didn't feel like heading to the Common Room just yet, so she started wandering around aimlessly in the shadowy corridors. When she grew tired of that, she stopped and sat down in front of one of the tapestries decorating the walls and hummed to herself, trying to calm her nerves. It worked for about two minutes, then she jumped up again and started pacing back and forth in front of the wall, muttering to herself. She just wanted to find Nathan. She wasn't sure why it was so urgent that she find him, but Rose couldn't stay still until she knew something about his whereabouts.

She almost didn't notice the door. She was so busy sulking and mentally sending everyone to hell that she was already around the corner before she realized what happened. Rose spun on her heels and ran back to the tapestry - or rather, where the tapestry used to be. In its place now stood an ornate wooden door, at least twice Rose's height, with brass knockers shaped like a phoenix. Rose hesitated for a moment only before pushing on the door and opening it. She expected a loud creaking sound to fill the corridor and the room inside, and already cringed just thinking about it. She shouldn't have worried, the door swung wide in complete silence and closed on its own after she stepped inside. What she found though surprised her to no end.

She seemed to be in some kind of a ship, if the controls in the middle of the room were any indication. It looked nothing like the things she saw in sci-fi movies back at home, but it was close enough to make her certain she stood inside some kind of control room that very probably belonged to a ship. Hogwarts doesn't have electricity, nor anything else that would be controlled by complicated machinery, Rose reminded herself. At least if she believed Clara who read Hogwarts: A History at least fifteen times. Which she did, simply because Rose herself never even picked up the book and her knowledge about the castle and its grounds was patchy at best.

"So, where am I then? And more importantly, why am I here?"

Rose jumped, but didn't take a step back as the ship came to life, whirring and flashing its lights, giving out strange metallic sounds that somehow mixed in well with the golden glow the room emitted.

"Alright. Are you saying hello? Well, um… Hello, I guess!"

She waved awkwardly and was about to chastise herself when the lights changed from golden to honey and the flashing of the lights became slower.

"Oh. You were saying hello! Fantastic!" she allowed herself a grin as she realized he borrowed Nathan's favourite word. Maybe because she knew he'd love this.

"So, are you gonna take me to Nathan? 'Cause I really want to find him!"

The ship whirred loudly and some of the lights dimmed, leaving a bright path between her and the console.

"You want me to drive? Not a good idea. I don't even have my license yet - and at this rate I never will. Dad says I drive like a lunatic. 'Tis probably true. I fly like a lunatic. Never made the Quidditch team either. I knocked the Keeper off his broom by accident. Nathan says I'd be a wicked Beater."

She smiled her tongue-touched smile and walked over to the controls.

"So, where to then? I guess I'll just flick," she hovered her hand above the console, palm itching, then chose at random, "this switch."

The ship groaned and she fell backwards, clutching at the railing as everything seemed to be shaking around her. It was over within a few seconds, but Rose stood gaping for many more, trying to come up with something to say over the ship's driving skills. It flashed its lights orange at her, as if it read her thoughts.

"I was supposed to drive, wasn't I?" Rose asked sheepishly. "Right. Gonna tell my dad he's probably right about not wanting me to have the license."

Rose walked around the console, stroking the buttons and switches lightly, about to flick another set of controls when the ship flashed its lights orange once more.

"What? Do you mean to say we have arrived already? Well, that's bollocks. We haven't even moved! No, you don't get to sass me! I get enough of that with Nathan, thank you. I don't need it from you too!" she shouted as the ship whirred and flashed its light in a manner that resembled laughing.

"Fine!" Rose threw her hands up and stomped towards the door, huffing when it opened easily.

"You want me to go outside then?" she turned without taking a glance at what lay outside. "Alright, then I can at least walk back to my dormitory and leave you in peace!" She took two steps towards the door, then turned back. "Do you think that was a nice prank? To make me think you could help me find my friend?! Do you? Because I really wanted to find him you know…"

She gasped when she realized tears were rolling down her cheek. For all her friends' teasing, she knew she fancied him. Had known for a long while. From about third year to be exact. But their friendship worked so well and she didn't want to risk losing him by confessing her infatuation. So she stayed silent. She didn't say a word when he fell off his broomstick and lay in the hospital ward. She didn't say anything when her friend Mickey died the year before and he stayed by her side the whole time, holding her hand, hugging her and whispering soothing words into her ear. She didn't tell him when he asked her if she thought he should start dating Lynda. She couldn't speak up when Jack asked her out and she refused.

He was always busy - everyone knew he was the smartest person in their year (if not in the whole school) and he was teased mercilessly by everyone that the Sorting Hat was wrong for once and should have put him into Ravenclaw instead. He took studying much more seriously than Rose did, and all the better for him. Rose imagined she'd end up a secretary or a shop assistant or some other menial job that would pay the bills but would leave her heart cold. Nathan could be anything he'd want to be after leaving school. He always talked about travelling (and Rose's heart always sank at the mention of him leaving the country), he could do that if he wanted.

With their sixth year beginning in September, Nathan seemed to be busier than ever. He was always running to classes, out of breath, barely able to say hello to Rose before he disappeared again. In the six weeks since classes begun, she only had a proper conversation with him once. It was very late and she snuck out with Amy to see if they could crash a party in Ravenclaw Tower, but the riddle they had to solve to enter was too difficult, so they gave up after a while. Amy went off to look for Rory in the Hufflepuff Common Room and Rose wandered back to Gryffindor Tower, too tired to look for another party. She stumbled across Nathan by mistake - well, sat on him by mistake to be exact.

Rose wasn't looking where she was going, barely able to keep her eyes open and collapsed onto the couch. As it turned out, the seat before the fireplace was already occupied. She stammered and apology and was ready to head up to her room when she realized it was Nathan. They ended up staying in the Common Room until six in the morning when the first students rose and made their way down to the Great Hall for breakfast. Rose was floating on a cloud for a whole week, but quickly lost her good mood when Nathan told her he wouldn't be coming for the Quidditch trials. He seemed genuinely sorry when she told him she'd be trying out for Chaser, but he ran off before she could ask what was so urgent that he couldn't spare two hours. And they hadn't talked since - two weeks ago now -, not even once in the Hall or in the corridors. Once she stayed up for a whole night in the Common Room just to see if he'd come, but she had no luck. No matter how much she wanted to be angry at him for ignoring her, she missed him too much.

Brushing her tears aside, she controlled the urge to kick the walls of the ship and stepped outside. Her jaw dropped as soon as she took in her surroundings. The circular walls, the dark wooden table, the cabinets full of magical things she'd never even heard of. Full of things she knew only from the gossip at the breakfast table and only half-believed. That was the Pensieve over there. And that… that must be the Mirror of Erised. No wait, they said that was not held at the Headmaster's office. Where was it? She couldn't remember. She all but stumbled outside, eager to hear and see everything. She could hear voices from the other end of the office, but from here couldn't make out what they were saying. She needed to get closer, but remain undetected. She didn't know how she'd even begin to explain to Dumbledore that she somehow just happened to appear in his office on a Friday afternoon, after stumbling onto a door that used to be a tapestry. Smiling she shook her head. Although that would surely not be the strangest thing the Headmaster has come across in his long life.

Inching closer to the stairs that led down to the rest of the room, she saw three figures standing just a few feet away from her - two of them had their backs to her, the Headmaster himself, and Professor McGonagall, head of Gryffindor; and one was facing the back of the office where she was hiding in the shadows. He was wearing the same red and gold uniform Rose had, but she couldn't see his face from where she was crouching. Moving slightly to one side, she let out quiet gasp as she realized it was Nathan. What the hell was he doing in the Headmaster's office?

"I understand, sir."

"You cannot tell about this to anyone, not even your friends. Not even Rose Tyler. Do you understand me?" McGonagall's strict voice drifted up to her.

"Yes, Professor. I will not tell anyone. Not even Rose." His expression looked a little pained at the last part and Rose scowled. If he couldn't tell her, that just meant she had to find it out for herself. She smiled her signature tongue-touched smile and leaned even closer, her muscles stretched to their limits as she tried to catch every word.

"I don't think there's need for that, Minerva. In his six years here, Nathan had been nothing but an exemplary student and I am quite sure that he knows the responsibility that comes with possessing a Time Turner."

Dumbledore seemed to turn his head a little towards Rose, but not enough to see her yet. She stared open-mouthed and couldn't shake off the feeling that the Headmaster knew she was there.

"I do," was Nathan's simple reply.

"Excellent. Just don't forget, no messing about with it. It is an extremely dangerous object to use and possess and could alter events so significantly that you could undo your own existence." McGonagall's voice came out less severe than moments before, but the edge never disappeared completely from it.

"I have no intention of playing with Time, Professor McGonagall. I know you think I might try to go back to say goodbye to, or worse, revive my family, but I won't. I can't say I'm not tempted, but I know full well I could do more damage than good and I will not risk it. I swear."

The head of their House nodded approvingly and left the room, while Dumbledore requested that Nathan stay for a bit. Rose didn't realize that this was her cue to leave until a soft chirp startled her. She turned around as quickly as she could and found herself staring at a baby bird swimming in ashes and flapping its tiny wings happily. She smiled as she realized that what she was seeing was a phoenix.

"Thanks. I'm gonna leave now," she whispered to it, reaching out a hand to stroke its head.

She hurried back into the ship and hugged one of the pillars tight before walking over to the console and pushing a few buttons.

"So, we went back in time, I presume?" she was still uncertain about what happened, but it was the only solution she could come up with. The ship didn't react. "I'll take that as a yes? Well, I'd like to go to where Nathan is now. Is that alright?"

The ship whirred to life and flashed its lights happily at her.

"Okay. Here we go then!"

With another flick of a switch, they were off.

A/N: Thank you for reading! Kudos and comments make my day and keep me writing, so if you've enjoyed this story, please leave one. The story has about 3 more chapters. I'm going to update weekly on Fridays.