Matter of Blood

Few days after Sirius' Birthday, the dreaded match between Slytherin and Gryffindor finally arrived. Claudia went down for breakfast and sat down with Lucy and Eleanor as far from the centre of the Great Hall as possible. She avoided sitting with Sirius and the other Gryffindors, as she did not want to give Regulus' stupid allegations any more legs.

No matter how much she tried to ignore the whole pre-match charade, Claudia could not help but glance at her replacement. Regulus looked ill. She remembered how she felt before her first game in charge and almost felt sorry for him. Almost, but not quite. All of this was entirely his fault.

Claudia could not quite believe her eyes when she saw what changes Regulus made to the team. Emilius would have been destroyed by the Gryffindors, so Julius' return to the team was no surprise and frankly, a bit of a relief. More controversially, it was Rowle's cousin who took Claudia's place as one of the chasers, and Creusa was not sitting with the team either. Instead, there was another guy that Claudia did not even recognise from the try-outs.

"Want to walk down to the pitch with us?" Eleanor asked, interrupting Claudia's brooding.

"I'm not going." Claudia whispered. "I couldn't bear watching it."

She excused herself and began walking back towards the Slytherin common room to pick up her books and hide in the library. But before she even set foot on the stairs leading down to the dungeons, Sirius caught up with her.

"I thought you might want this." He smiled and handed her a package which she knew instantly to be the invisibility cloak.

"What for?" She asked. "Everyone is going to be at the game. I could dance naked through the Great Hall and no one would notice."

"We both know that you're dying to see the game." Sirius chuckled. "You just don't want people to know. Analyse your every expression."

Claudia smiled back at Sirius and took the package out of his hand. He was right. She waited until the game was underway, put the cloak on, and went down to the pitch. Once there, she snuck through the changing rooms, found a spot by the foot of one of the pylons and watched.

The Slytherin chasers looked like they had never met each other before, let alone played Quidditch on the same team. Regulus was so distracted by shouting at everyone that he missed the snitch flying across his face. When he finally noticed the gleaming speck, he clumsily launched himself after it and slipped off his broom. The entire school laughed as he dangled from it in mid-air.

Throughout the game, Claudia's heart rate was higher than if she was playing. She recognised the manoeuvres that the team were trying to pull off, but was painfully aware of just how short they were falling. She knew that if she was still on the team, the game would be going very differently. Both Rowle and the other new chaser were utterly useless. It was torturous, just having to watch this.

Slytherin were over a hundred points behind when the Gryffindor seeker took pity on them, dived from a great height and caught the snitch. The Gryffindor end jeered as the Slytherin team left the field, dejected.

Claudia waited for everyone else to go back to the castle before she took off the cloak and climbed up to sit in the empty stands. The anger and stress she experienced during the game were replaced by a large void in the middle of her chest. It had been three years since she watched helplessly from the side-lines while the Slytherin team played, and it felt awful. She missed being out there. The wind in her hair, the rush of launching the quaffle towards the hoops and scoring, the euphoria of winning. She missed all of it. Even the dull pain in her muscles after the game, which used to make her feel like she left everything on the pitch. Like she accomplished something.

"That was truly terrible." Claudia heard Slughorn's voice from behind her. He must have been to the changing room to give one of his dreadful speeches. She missed many things about being on the Quidditch team, but she did not miss those.

"Awful." Claudia sighed as he sat down next to her.

"What went wrong?" Slughorn asked.

"Regulus is trying to change too much too quickly." She sighed. "They need to get back to basics. He needs to get Creusa back on the team. I don't even know why she wasn't playing. And Rowle needs to stop trying to prove himself and pass the quaffle sometimes."

"I'm sorry, Miss Avery." The Professor mumbled. "I fear you may have been treated rather unfairly in all of this."

"What's done is done." Claudia put on a brave face, but she was not going to forget Slughorn's role in her demise that quickly.

"I think I know a way to make this up to you." Slughorn's eyes twinkled. "I will be hosting a Christmas party. You and Mr Black should both come."

"A party?" Claudia raised an eyebrow. "Are you sure that's not just further punishment?"

"It's not the party that is the reward, Miss Avery." Slughorn smiled. "It's the company that comes with it. The best and the brightest."

"I'll await the invitation with bated breath." Claudia smirked.

"That's the spirit." Slughorn laughed and patted her on the shoulder. He clearly was not too good at picking out sarcasm. "I'll leave you in peace." He added and began walking back to the castle.

Claudia gave him a sufficient head-start to make sure she did not catch up with him and followed suit.

When she got to the Slytherin common room, everyone went instantly silent and stared at her. Half of them even had their mouth open in anticipation of what was to come.

"Could you try looking less smug?" Emmanuel barked.

"Don't take this out on me." Claudia scoffed. "I didn't make you throw all the tactics out of the window and make you look like fools out there."

"Well, you did." Rowle growled. "Of course, we had to change everything since you told the Gryffindors."

"If you believe that, you're even a bigger idiot than your cousin." Claudia barked at him. "And that's some achievement."

From one of the armchairs facing the fire, Claudia heard a sound as if someone starting clapping. In a slow and obviously sarcastic way. The rest of the team felt silent.

"Impressive performance, Avery." She heard the person say a moment before their head emerged into her field of vision and she realised who it was. "But we all know you are a filthy blood traitor." Regulus scoffed. "Who knows how long my brother has been fucking Quidditch secrets out of you."

Some of the team laughed. Claudia noticed Julius did not. Instead, he clenched his fists and looked away.

"This isn't on! Apologise to her." Chris stood up angrily, attempting to defend Claudia, but she gestured him to sit down.

"You're a delusional prick, Regulus." She scoffed. "And your delusions have cost us the cup this year. You should be really proud of yourself."

Claudia did not wait for a response and made her way back to the girls' dormitories.

"Fucking idiots!" She yelled when she got there. The composure she was trying to maintain in front of the team was gone and she kicked her bedside table in anger.

Her picture with the Minister of Magic that stood on top of it fell over and the glass smashed across the stone floor.

"Just what I need." Claudia whispered in frustration and took out her wand to repair it. But before she muttered the spell, she noticed a piece of parchment sticking out from behind the photograph. She dropped to her knees, carefully pulled it out from among the shards of glass, unfolded it and began to read.

TOP SECRET

From: A

To: The Minister of Magic

Handling instructions: Minister's Eyes Only

On the matter we discussed earlier, I implore you again not to underestimate the situation.

To set out what we know so far.

The 'substance' in question seems to trigger a subconscious physical reaction. The body starts attacking itself (this is where the immunity-boosting cocktail of echinacea etc. comes in) and the subject falls ill within twenty-four hours of consuming the concoction. Long-term effects are unclear.

As far as we can tell, it is largely up to the caster of the curse to determine how exactly he wants the subject's minds twisted once the potion is consumed. As an example, if the caster wanted everyone called Harold to fall ill, the concoction could do it. We think – and this is untested – it would make your mind feel such shame about your name that the body would start killing itself. The worse thing is that you would not even know. That is why they added lovage and Jimsonweed, to make the subject oblivious to what was happening.

I know politics is not within my remit, but I am begging you to consider the danger that this could pose to muggles and muggleborns, if 'they' can make it work. You must get the potioneer back or silence him forever. Whatever it takes, Harold.

You did not take my advice about not letting the Americans bring this into the country. But please listen to me now, I am begging you.

A

"Shit." Claudia whispered as she got to the end of the report. She crumbled the paper in her palm, grabbed the invisibility cloak and run towards the Gryffindor Tower as fast as she could.

Snape was not trying to kill her after all.

It was much worse. So much worse.

"Come on. Come on." She whispered to herself as she waited, hidden under the cloak, outside the portrait guarding the entrance to the Gryffindor common room. "Somebody, come out."

She did not have to wait for long. Barely five minutes later, a couple of Gryffindors stumbled out of the common room looking for a quiet place to snog.

"Come with me." Claudia whispered into Sirius' ear when she found him in the common room and tugged on his arm in the direction of the dormitories.

He grinned, excused himself, and followed her up the mahogany staircase.

Claudia shut the dormitory door behind them and threw the cloak off.

"This kind of surprise visits I can get used to." He whispered and pulled her in for a kiss. But they did not get to it.

"I know what Snape's concoction is." Claudia blurted out.

"How?" Sirius asked and let go of her.

"Someone left this in the photograph I got at the Ministry." Claudia handed him the crumbled piece of parchment. "It must have been Ignatius."

Sirius unfolded it and began to read. The further he got, the more he frowned.

"No." He whispered when he got to the end and looked up at Claudia with horror in his eyes. "It can't be."

"It fits." Claudia replied. "Echinacea, lovage and Jimsonweed are all mentioned. Lucy and Eleanor are both muggleborn. It explains why no one else got sick. And the potioneer this memo refers to must be the person who got kidnapped from these American talks. It all fits!"

"But how does Snape have it?" Sirius asked.

"My father. He was the one who set Marcus these inferi tests, remember?" Claudia whispered. "He must be doing the same with Snape. After he kidnapped the potioneer from the talks, he's made him produce this thing and now he's having Snape test it here at Hogwarts. It's Snape's rite of passage to the Death Eaters."

"Fucking hell." Sirius sighed. "I'm going to get the others. And Dumbledore."

"Not Dumbledore." Claudia said instinctively.

"What do you mean?" Sirius frowned. "We have proof. He needs to know."

"Please." Claudia whispered and shook her head. "Not yet."

"I know you're mad at him." Sirius growled. "But this is bigger than some dumb gripe over who got to be Head Girl."

"Just give me a minute." Claudia barked at him. "I need to think."

"I'm going to get the others." Sirius said resolutely. "You have about two minutes to figure out why it's a good idea to keep this to ourselves." The tone of his voice made it crystal clear. He thought she was being crazy.

Claudia's mind began racing the moment Sirius left her alone. It was not that she did not want to tell Dumbledore, she just hated acting on impulse and this needed thinking through.

"What would Dumbledore do?" She mumbled to herself.

The wheels in her brain began to turn. He would probably get Snape arrested and interrogated, and You-Know-Who would know instantly Dumbledore was onto him. That could be a problem.

On the other hand, if Dumbledore knew, he could use his network to help the Minister find this American potioneer. Then again, the Minister knew about all of this already. Was Dumbledore really that powerful? Could he really pull strings that the Minister could not?

"Arrrgh." Claudia growled and kicked the leg of one of the beds. "This is impossible!"

Her toe was still burning with pain from the impact when Sirius and the others walked into their dormitory. James in particular looked rather bemused as to why his Quidditch celebrations were interrupted.

"I don't want to ruin your party." Claudia whispered and moved towards the cloak, ready to leave. When she saw them, all lined up there, she was not even sure whether she should be telling them, let alone Dumbledore. "Why don't you go back to celebrating, and we can talk about this tomorrow."

"You look like a ghost." Remus whispered, sounding worried. "What's going on?"

Claudia took a deep breath. It was too late to change her mind.

"Read this." She passed the piece of parchment to Remus. Only then, she noticed that her hand was shaking. James and Peter huddled around him and they all began to read.

"What does it mean?" Peter spoke first.

"Is this the reason why people are getting sick?" Remus whispered. "Have they all been muggleborns?"

"I think so." Claudia nodded. "Lucy and Eleanor certainly are."

"Sickening." James whispered, white as a sheet. "I cannot believe that something like this exists. That Snivellus of all people has it."

"Do we think they've tried it in the real world yet?" Sirius asked. "Or are they waiting to see whether it works?"

"The latter, I would think." Claudia replied. "You can't control the experiment outside. Hogwarts is perfect for testing this. You know who's a muggleborn, you know exactly when they get sick, and who is treating them."

"What are we going to do?" James sighed and sat down on his bed with a thud.

"We could destroy the potion." Sirius mused. "We know where Snape keeps it."

"Wouldn't make a difference." Claudia shook her head. "They can easily make more."

"Can we make them think it doesn't work?" Remus asked.

"That's a good idea." Sirius pitched in. "Mess with the testing. We could make some kind of antidote to protect the muggleborns."

"Or we could poison some purebloods." Claudia nodded along. Remus chuckled, and so did James.

"Cute that you still think Claude's joking when she says things like this." Sirius smirked.

"You cannot be serious." James' expression changed into a frown and he exclaimed towards Claudia. "We cannot stomp to their level!"

"Whatever we do." Claudia shot Sirius an annoyed look. "We cannot tell anyone. Not McGonagall. Not Dumbledore."

"Why?" Remus asked. Claudia glanced towards Sirius again, who was staring at her with his eyebrows raised. He clearly could not wait to hear what she came up with.

"Because if we do, they'll put a stop to it…" Claudia began to say.

"And that's a bad thing, why?" Sirius quipped.

"We need time to make my father think it's not working." Claudia replied. "If we tell the teachers, we won't get that time."

"But people are getting hurt." James barked. "Are you saying we should let that continue?"

"It's a price we need to pay." Claudia whispered. "It's the only way."

"You're forgetting my girlfriend is muggleborn." James replied through gritted teeth. His reaction to the whole thing suddenly made a lot more sense. "She's not some pawn whose life you can risk. This is not wizard chess, Avery."

"What do you suggest we do?" Claudia barked.

"I don't know." James stuttered. "There has to be another way."

But there was not. They sat on the floor of the Gryffindor boys' dormitory until well after midnight, going through every option and scenario. And they did not come up with anything better.

As a compromise, the boys agreed not to tell anyone for the time being, and Claudia agreed to pursue the antidote and forget about the poison.

Both of those things, however, were exceedingly hard. They were all sitting at breakfast together the following day, and not one of them looked like they had a wink of sleep. All they managed was to eat their food in silence.

Claudia kept glancing towards James. His fists were clenched around his spoon and he kept glaring towards where Snape was sitting at the Slytherin table. Claudia could not remember whether she had ever seen this much hatred in someone's eyes.

"Can we please remember to keep our heads, act normal and leave Snape alone?" She whispered urgently.

"If we were acting normal, we would not be leaving him alone." Sirius smirked. No one replied, but they all frowned at him. Now really was not the time for stupid jokes. "Fine." Sirius rolled his eyes. "We will leave him alone."

A Tawny Owl that Claudia did not recognise dropped something into her lap. Better not be another letter from my mother, she thought. She got plenty of those since she left home. Some were begging her to come back, some were threatening her, some just read like nothing had happened. The last one was almost laughable. Cassandra wrote about all the plans she had made for Christmas, not even acknowledging that Claudia might not be coming home for the holidays.

Claudia did not reply to any of her mother's letters. In fact, she did not even finish reading most of them before incinerating them right in the middle of the Great Hall. But this letter was not going to meet the same faith. It was from Alice.

Dear Claudia,

I should have known that you will be terrible with letters! I have some news and got sick of waiting for you to reply to my last one, so here we go.

You were so right about Joseph. I did not quite know what it was supposed to feel like to really like someone, let alone love them. I only realise it now because, well, I kind of think I have fallen for someone!

I have met him at work. His name is Frank. He was few years above me in Hogwarts. He is smart, funny, kind. We have only been on a couple of dates, but I can barely think about him without getting butterflies in my stomach. He is making me so giddy. You would think I have lost my mind.

You need to meet him! Let's organise something for Christmas. Please tell me you're coming back to London!

What is the news from Hogwarts? Has everyone got over the fact that you are dating Sirius? Are you staying out of trouble? I am dying for news here…

Alice

Claudia stared at the parchment. She was happy for her friend, but the letter felt like something from another world. A world full of love, happiness and laughter. A world that Claudia, after yesterday's discovery, no longer recognised.

"Ready?" Sirius interrupted Claudia's train of thought.

"Sorry." Claudia mumbled. "I wasn't listening. For what?"

"I thought we could all go to the Slytherin's apartments to talk in private." He whispered.

"Sounds like a plan." Claudia sighed and stood up.

"We will figure this out, Claude." Sirius whispered, put his arms around her shoulders and kissed the top of her head. "These bastards won't know what's hit them."

Claudia allowed herself a tiny smile. Sirius was right. He and his friends were borderline geniuses. They all managed to become animagi by the time they were sixteen, and the map was quite incredible too. And she was not exactly a waste of space either. She was better at potions than most and certainly had more experience fighting dark wizards than you would expect from a seventeen-year-old kid.

"What is this place?" James asked, looking around Slytherin's study.

"Slytherin used to live here." Sirius smirked. "It's perfect for a new base. No one knows about it, so we won't be disturbed."

"What's behind there?" James added, nodding towards the curtains that were concealing the door to the bedroom.

"Just storage." Claudia intervened. She was not going to let them take over the one place in the castle where she and Sirius could find some peace.

"Good shout." He whispered in her ear when the others went to fetch a table and some chairs that were standing broken in the corner of the room.

Remus was the first to speak once they were all sat down, ready to begin.

"I think we can safely rule out the Antidote to Common Poisons. But I think the Antidote to Uncommon Poisons would be a good place to start." He opened a textbook and began to read. "The ingredients required are fire seeds, graphorn horn, billywig stings and chizpurfle carapaces."

The boys began to discuss where and how they could obtain the ingredients. Fire seeds could be obtained relatively easily from the Herbology Greenhouses. Graphorn horn was going to be tricky, but Sirius volunteered to investigate the black market over Christmas. Billywig stings were used in Wideye Potion and easily obtainable. Chizpurfle carapaces were going to be bit of a nightmare, but doable.

"It looks fiendishly complicated to make though." Remus frowned. "Even if we manage to get all the ingredients."

Claudia reached across the table and pulled the book towards her.

"I can easily make that." She uttered as she scanned the page. "But it's not going to work."

"What makes you say that?" Remus asked.

"For a start, it's not a poison. It bends your mind. And we don't need an antidote, but something to prevent the symptoms. Antidotes work once the poisoning has happened." She replied.

"Fair enough." Remus whispered. "Let's keep looking."

So they did. Every free period they had and every single evening, they convened in the Slytherin apartments. They did their NEWTs work and antidote research. On the latter, however, they were getting nowhere.

Claudia did not quite have the heart to tell them that even if they found something that could potentially shield people from the effects of the substance, they would have no way of knowing if it was working or not. It would be impossible to track who consumed the antidote and who was being poisoned by Snape's concoction.

Flooded with work and guilt, Claudia kept finding excuses to postpone replying to Alice's letter. She hated the idea of going back to lying to her friend about what she was really up to, but she had no choice. Alice, her best friend, may have just about understood but Alice, the trainee auror, would not hesitate for a second before reporting this to the authorities. With that thought in mind, Claudia picked up a quill and began to write.

Hi Alice,

I'm so happy for you and cannot wait to meet Frank when we're back in London for Christmas. I promise to try not to scare him away (if I decide that he's good enough for you… haha).

Everyone had a bit of a meltdown about me and Sirius at the start, but it's getting a bit easier. Except Regulus got me thrown off the Quidditch team. He convinced Slughorn that I told Sirius our Quidditch tactics, which is obviously rubbish.

At least I have plenty of time to study now. No practices, no tactical sessions, no games. I didn't even realise how much time this used to take. The NEWTs are an absolute nightmare, but your stories from the auror office are keeping me going.

See you soon!

Claudia

That would have to do, Claudia thought as she made her way to the Owlery. She knew she was risking Alice's friendship over this, but she did not feel like she had a choice. There is no way she could have put this on Alice's shoulders and ask her to keep it to herself. It had to be this way.

About a week before everyone was to go back to spend Christmas with their families, Claudia had Slughorn's party to attend. Given the circumstances, it all seemed rather pointless. Sirius took a lot of convincing and only agree to come along, when James twisted his arm. He too was coming with Lily.

"I finally get that double date you promised me." Lily said as the couples met in front of the Great Hall before heading to Slughorn's apartments together.

"I've never promised you anything." Claudia uttered.

"Well, that's not how I remember the conversation." Lily replied, her lips pressed tightly together. She grabbed hold of James' hand and set off towards the party.

"This is going to be a fucking long evening." Claudia whispered to Sirius and followed them.

"This will help." Sirius smirked and took out a hip flask from his robes. He opened it and passed it to his girlfriend.

"I take that's not pumpkin juice." Claudia smirked and took a sip. The back of her throat kept burning until they got to the party. It was definitely not pumpkin juice.

The party was just as Claudia expected. Cold, tasteless food that was clearly designed only to look pretty, cheesy Christmas music, and - worst of all - it was full of the straightest and snottiest students that Hogwarts had to offer. Even that insufferable prick Lockhart somehow managed to get hold of an invitation, despite only being a third year. He was currently boring Slughorn with his intention to captain England's Quidditch team to World Cup glory, before knuckling down to becoming Britain's youngest Minister of Magic.

Claudia and Sirius were watching him with amusement, sharing the fire whiskey Sirius smuggled in. Unfortunately, that light entertainment did not last long, and they soon found themselves in the company of Claudia's favourite Slytherins.

"Look what the cat dragged in." Regulus smirked.

"Shut up and get lost." Sirius barked.

"Or what?" Regulus frowned. "Are you going to punch me again?"

"You bet." Sirius took a step towards Regulus, but Claudia grabbed his arm just in time and pulled him back.

"You two have really found each other." Regulus sneered. "Pair of bloodtraitors."

"I'd rather be a bloodtraitor than what you've turned out to be." Claudia replied, her fists clenched and brows together. She was slowly regretting stopping Sirius earlier. "Why don't you leave us alone and go talk to the other baby Death Eaters."

Regulus froze, just for a fraction of a second.

"Wanting to maintain a proper order of thing, doesn't make Reg a Death Eater." Julius, who was with him, replied.

"Proper order of things?" Claudia scoffed. "You've changed your tune."

"It's not the only thing I was wrong about." Julius replied, leaving everyone in no doubt that the other thing he was wrong about was his relationship with Claudia. "Let's go, Reg. They aren't worth talking to."

Regulus gave Sirius one more evil smirk and followed Julius back into the crowd.

"What did they want?" James asked, as he and Lily finally arrive with the drinks.

"Causing trouble as usual." Claudia sighed and glanced at Sirius. His eyes were still flaming with disgust. It only just dawned on Claudia that she called Regulus a baby Death Eater, and Sirius must have noticed his reaction too. There was no denial. No shame.

"I hate what became of him." Sirius finally spoke and took another swing from his hipflask. "Arrogant, pompous ass. Just like the rest of the family."

"It's this war. He's not the only person that has changed." Lily whispered. "It's just like Severus."

"Snivellus has always been a slimeball obsessed by dark magic." Sirius replied.

"No, he hasn't." Lily said, frowning at him slightly. "We used to be friends."

"Were you?" Claudia asked. "I didn't know he had any friends."

"We grew up close to each other. He was the one who told me I was a witch." Lily whispered. "He was a kind, shy kid from an awful family. We stayed close after we got here, but a couple years back, something changed."

"He started to hang out with my brother, that's what changed." Claudia sighed. "Got his head turned by the nonsense."

"I still believe there is good in him." Lily smiled. "One day, he's going to realise he has made a huge mistake. He will change, I'm sure of it."

"I rather doubt that." Claudia smirked. If Lily knew what Snape was up to, she would not be saying such nonsense.

"Can we please not go there?" James groaned. Claudia was getting the impression that it was bugging him, keeping things from Lily. But Lily was not deterred.

"I do not understand how you can go through life thinking people cannot change for the better." She barked with the slightest glance towards Sirius. They were not talking about Snape anymore, that was clear.

"Mind your own business." Claudia hissed back.

"Excuse us." Lily tugged on James' sleeve. "We need to find Professor Slughorn and thank him for the party."

"What was that about?" Sirius asked when James and Lily got out of earshot.

"Do you know how she is always trying to fix things?" Claudia said. She was still frowning but was getting her temper somewhat back under control. "Well, I think we're next on the list."

"Oh boy." Sirius chuckled. "She's got a big job on her hands."

"She's a nightmare." Claudia sighed.

"Come on, she isn't that bad. You're both just…" Sirius paused, seemingly weighing his words.

"Tread carefully, sunshine." Claudia hissed.

"Anyway." Sirius chuckled. "This party is awful. Really brings back the memories."

"Room full of people with sticks up their asses?" Claudia asked.

"That. And my brother being an asshole." Sirius added and opened his flask again. "And me sneaking in the drinks to make it manageable."

"I know what you mean." Claudia sighed. "All that's missing is my mother trying to set me up with some bore."

"Bail somewhere more private?" Sirius whispered and slid his hand down onto Claudia's hip.

"Is that how you used to get out of your parent's parties too?" Claudia smirked and hung her arms around his neck. "Find someone to make out with?"

"No comment." Sirius chuckled and kissed her.