Lia shivered. As fall gave way to winter, Hogwarts had gradually become frostier and frostier.

It was alarmingly cold, even despite the thick woollen coat that she had flung across her shoulders during the seconds before she'd burst out of her room, realising that she had been late to meet Harry, Ron and Hermione. Her cheeks were now flushed from her run down to the yards, her hair whipping wildly in the wind.

Lia made a mental note to teach herself a warming spell next time, or at the very least buy some more sweaters. She didn't want hypothermia. She supposed that she could make a fire, but she had no container to put it in. And it wouldn't really work on the snowy ground, would it?

It was the beginning of the new Quidditch season, and on Saturday her brother would be playing against Slytherin.

It was pretty unfortunate that he was up against her own house for his very first match. Marcus Flint was renowned for his aggression, and his team was made up of burly, grunting boys that wouldn't hesitate to commit a foul as long if they thought that it would give them an advantage.

Lia was also having a hard time dallying between Harry and her new Slytherin friends. Some, like Tracey, had accepted that regardless of how hard they tried to push and persuade, Lia wasn't going to just ditch her brother because of some stupid house rivalry that had existed long before she was even born.

On the other hand, Lia was also unwilling to lose the relationships and standing she had gained in Slytherin house. She was close enough now with Tracey that she could trust her fully, and she thought that Caroline and Selene usually had her back; but she didn't expect any of them to be happy if she started cheering for Harry in the match.

It was just so hard.

At first, most of the Slytherins had been more than happy to torment a Potter. Their harassment had lasted for about a week, before Lia had finally snapped, lost it, and sent Blaise Zabini and Millicent Bulstrode to the hospital wing, transfigured into half-human half-slug monsters. It had taken another delightfully humorous week before Madam Pomfrey had been able to reverse the effects of the hex. Better yet, since Lia had carefully made sure that Zabini and Bulstrode would be able to find no evidence against her, she got off scot-free.

After that, the Slytherin bullies had been sure to be more careful with their words, and had mainly stayed out of her way. Once, Zabini had even given her a look of grudging admiration and asked her what incantation she had used. Lia obviously wasn't going to be so stupid as to tell him. She'd basically be asking Blaise to use the spell against her, so she had just given him a girlish wink. He'd looked flabbergasted.

Malfoy and Parkinson were another story entirely though. She didn't think that she would ever be free from the two's incessant yapping in her ear. They'd tried so much: hexing her behind corridors, which had worked the first time, but their glee quickly faded when Lia said the counter-hex about five seconds later (To avoid having that happen again, Lia now walked around with her wand in her hand in case she had to cast a split second shield charm); snapping insults every time they saw her, although Lia always had a wittier comeback up her sleeve; and now they were tripping her over before class.

It was a bit pathetic.

One time, they had even attempted to get some older Slytherin boys to intimidate her, but Lia could be scary, and now they trembled every time she made eye contact with her. Lia had even learnt how to do a simple stinging jinx without her wand, in case a miracle happened, and they were actually smart enough to think of disarming her.

She had to admit, the good thing about being Malfoy's enemy was that she was constantly pushed to work harder, to learn more spells, so she could always be able to defend herself.

Quirrell had even remarked on the fact that her skill in Defence Against the Dark Arts was at a fourth year level. After seeing her send a book flying through the brick wall of his classroom from a mere, 'Flipendo', or knockback jinx, he had told her to see Snape about her timetable, and find if she could sit in on another class with the older students.

Harry had been famous as soon as he stepped foot in the school. But Lia was now rapidly making a name for herself as well. Now, when people talked about her brother, she wasn't always exempt from the conversation. She thought that a lot of people might have been scared of her – she was a Slytherin, they were notorious for their cruelty, and even though this was her first year, she was able to perform an assortment of somewhat dangerous spells.

She had heard the whispers in the corridors. Some admiring. Some envious. Some fearful. And some angry.

Graham Montague had remarked on how it was ever possible that a girl with a mudblood mother could become so formidable. Lia had been offended, but also a bit satisfied when she'd heard that he'd called her 'formidable'. Considering that it was Montague, Lia almost took it as a compliment. Of course, he had called Lily Evans a mudblood, so no-one was particularly shocked when his hair magically became white as snow the next day, and he sprouted a curling white moustache to match.

Hermione had been jealous of Lia at first. She didn't understand how she had time to study and learn all these incantations when she was always running around pranking Malfoy or teasing Harry. Lia had told her, when Hermione finally found the courage to confront her, that she wasn't actually that smart. Not as smart as her, at least. And she had shown her a copy of her History of Magic grades as proof. She had gotten a 'dreadful' on the previous, hastily written, last-minute essay.

"I'm just good with magic," Lia had said candidly. "Nothing else really. I think I do despise numbers and dates. And Binns bores me to death."

Her eyes had then lit up. "I know! How about this. Hermione, you tutor me in Astronomy, History of Magic and Herbology. So then, I'll help you with Transfiguration, Potions, Charms and Defense Against the Dark Arts. It would be perfect! You in?"

Her friend had nodded swiftly.

"Although I'm not really sure if you need any help." Lia laughed. "Not from me at least."

"Don't be modest," Hermione had said.

Presently, Lia, Harry, Ron and Hermione were strolling through the courtyard. It was quite chilly out, but Lia wouldn't give up the opportunity to spend time with his brother's group. Besides, Tracey was sick, Daphne was preoccupied with sucking up to Pansy, and Caroline and Selene were off doing god knows what. Hermione had conjured up a bright blue fire, that they'd put into a jam jar. She had used a spell that Lia had taught her.

It was at the exact moment when she had pressed her hands against the sides of the jar, seeking a moment of warm bliss, that Snape crossed the yard and saw them.

Lia didn't really know how she felt about the hook-nosed professor. On one hand, he hated Harry for no real identifiable reason, all the while treating Draco like he was the Prince of England. On the other, he wasn't horrid to her, and he had admitted half-heartedly that the Potter girl wasn't as much of a failure as her brother.

Lia thought that he was sometimes torn between his desire to give points to his own house (for Lia's potions were always immaculate, and deserving of praise), and his apparent rampant loathing of anyone whose last name was 'Potter'. Lia knew this from the multiple times that he had insulted James Potter to Harry's face, during which her brother would always be unable to hold back his temper. She wasn't sure how he managed to finish his homework, with all the detentions he got.

With the care and detail that Lia put into her potion making, with the patience and dedication that surprised even her, the biased Snape had to give her points for her hard work. Unfortunately, he had found himself a solution to his conundrum and now often took the liberty of pairing her with Malfoy during group work. His ability in potions was alright (quite good if she was honest), so Snape could just give Malfoy points for their combined finished work, whilst ignoring Lia. She supposed it could be worse, and she was thankful that Pansy's skill in potions was almost as bad as her looks.

Malfoy wouldn't really talk to her much in potions class. One time, he had accidentally brushed his hand against hers, jumped back as if he'd been burned, and glared at Lia like it was somehow her fault.

"Don't worry, Malfoy," she had said, feeling a tad vexed. "I don't think it's possible for you to catch anything that you're not already suffering from."

Overall, Lia was still reserving her judgment on Snape. He was a peculiar man, and she wanted to wait until she finally got to the bottom of things. No one could hate someone, at least not the way Snape hated Harry, unless there was some reason, some backstory. Moreover, she sometimes saw the professor look at her with stunned recognition before he shook his head and walked off.

Now, with Lia's hair down, and billowing across her face, and her eyes liquid gold from the happiness that only true friendship could give her, Snape had indeed thought that she had resembled a woman he had once known.

"But it couldn't be," he wondered, shaking his head. He walked over to the four. They were all looking awfully suspicious.

As he crossed the yard, Lia noticed that he was limping - leaning slightly harder on one of his legs.

"What is it that you've got there, Potter?" he demanded.

Harry showed him his copy of Quidditch Through the Ages.

"Library books are not to be taken outside the school," Snape said coldly. "Hand it over. And five points from Gryffi-."

"Professor," Lia said, faking embarrassment and hesitancy, cutting Snape off before he could finish. She knew that he wouldn't be able to bare to take points away from his beloved house. "That's actually my book. I thought it might be beneficial to read up, you know. Before our first game on Saturday! I'm sorry for breaking any rules. I can really be quite scatter-brained." She shot her best puppy eyes up at Snape.

He looked aggravated. "Don't do it again. This is a warning, Miss Potter." Snape spun around and walked off, with a slight stagger.

"Thanks," Harry said, once the potions master was out of earshot.

"What are sisters for?"

"He must have made that rule up," Harry mumbled.

"Did you see his leg though?" Lia asked. "He was limping."

"Good," Ron said, who still bitter about Snape's blatant prejudice against Harry. "I hope it's really hurting him."

At night in her common room, Lia checked over the piece of parchment by her desk and saw that a new sentence marled the paper, in her brother's messy scrawl. She had enchanted it, the corresponding page placed in Harry's room, so that they would be able to communicate at night during emergencies, despite the fact that their common rooms were spread far apart.

"Meet me in front of the Gryffindor common room tomorrow at 6:45am. We must talk about S," it said.

Lia pondered for a minute. S would probably be Snape. She suspected that Harry had found another piece of 'evidence' against him. She thought that Snape was probably up to something as equally mysterious as it was suspicious, but she didn't believe for one second that he was actually evil at heart. She didn't completely understand why she had this opinion, but her gut and her heart told her that the professor was innocent.

Lia's suspicions were proven right the next morning when Harry launched into a long rant about how he had heard Snape talking to Filch.

"Do you know what this means," Harry said. He was breathless, and currently waved his arms around like a chicken. "He tried to get past that three-headed dog at Halloween! That's where he was going when we saw him - he's after whatever it's guarding! And I'd bet my broomstick he let that troll in, to make a diversion!"

Lia yawned. "I can't believe I woke up half an hour early just to hear your paranoid rambling. For gods' sake, Snape's a professor. I highly doubt he's trying to … I don't know. Unleash destruction? What is it you think he's doing anyway? And besides, he can't have let that troll in. He was sitting just beside Dumbledore, remember?"

"No," Harry said stubbornly.

"In fact," she continued, "The only person not present at the feast was … was Quirrell," Lia trailed off. But it couldn't be Quirrell now, could it? That was certainly a laughable idea. The man didn't look like he could harm a butterfly. Let alone be brave enough to make eye contact with a troll.

But then again, looks could be deceiving. She should know that.

For example, Malfoy looked decent when you first saw him. But, no. The illusion would be all ruined when he spoke in that annoying high pitched, whiny voice. Then you'd realise that the boy was just completely full of crap.

Harry's voice broke her train of thought. "You have to believe me Lia. I'm telling you he's up to something. And I need your help to stop him!"

"I know, I know. I believe you, Harry. Well, mostly. I do think Snape's planning something. Look. I'll promise to keep an eye out okay? And I'll tell you as soon as possible if I see anything worth mentioning. Now, look at the time! We have to go to breakfast."

"Alright," Harry said, but he didn't look completely appeased.

The two siblings walked off in the direction of the Great Hall.