The days after Avery's poor attempt of gathering information went by quite eventfully. Not only had Avery and Lestrange almost gotten expelled by Dippet for what they had done, but had received the worst detention you had ever heard of.

Every day, up until the N.E.W.T.s would start, they had to help Mr Carpe, Hogwarts' caretaker, to clean every last bit of the castle. Without magic of course. And when they weren't scrubbing floors, cleaning windows, or polishing trophies, they were copying the school rules on parchment, by hand. The amount of paper they had to fill looked like it wouldn't even fit into an entire classroom, had it not been rolled up.

Even if they still wanted to, their new schedule didn't even give them enough time to trail, or even think about you. They barely had enough time to finish their homework before tumbling into their beds.

You would have felt sorry for them, but Tom's snarky grin, which he wore every time you saw the two in the hallways, reminded you that you didn't have to.

Thank Merlin you hadn't told Avery much when he had disguised himself as Tom. You had just confirmed that the engagement had been arranged but thankfully hadn't said anything about your sister. There had been worse rumours going round about Tom and you.

Camille almost didn't believe you when you told her what they had done. After a lot of head shaking and "no, they didn't"s she just stared at you with her mouth open and proceeded to laugh for a full minute or two when you told her about their punishment.

It was a lucky coincidence that she had found an interest in Ben, as she didn't mind now that you were spending a lot more time with Tom. She was preoccupied as well by the looks of it.

After the accidental sleepover, you had stayed in Tom's dorm overnight more often. Not on accident though. It had become a routine to you, to have another quick chat with Camille after classes, arrange some dates for when you wanted to study together and then make your way to the Slytherin common room, where Tom's dorm was.

Tom was sitting at his desk when you entered the room, apparently deep in thought and studying the Potions book he had gifted you.

"Alright?" you said when you closed the door.

He nodded as you went up to him.

"Found anything interesting for the Moly?" you asked. "It still looks quite healthy to me."

"Not really," he answered and turned towards you. "Nothing specific."

"Oh, I just got an owl from my parents. " You crammed the letter out of your bag and handed it to him. "They've fixated the date. For the wedding."

Tom read the letter quietly, his eyebrows twitching slightly once or twice.

"June 30th," he said.

"That's only one day after we graduate," you stated and tried to lighten the mood by joking. "Seems like they can't wait for the big day."

He nodded as he gazed into the flames inside the fireplace, a tiny grin pulling on the edge of his mouth before he looked up at you. "Can you?"

To prevent the chuckle that built up inside of you from bursting out, you took Tom's hand, lightly pulled on it and gestured towards the couch, where you wanted to sit. He closed the Potions book, but kept one finger inside it and took it with him when you led him over.

"Well, I don't know," you said as you let yourself fall onto the cushion. "It still doesn't feel real, does it?"

"True," he simply agreed.

"I can't wait to try on the dress, though. That'll be exciting," you went on and noticed him smiling. "And then there's the most important part, of course."

He gave you a look as if to say he didn't know what you meant.

"Elsie," you explained. "Your uncle will lift her curse completely then. Or so I hope at least."

Morfin had to, didn't he? It was part of the pact after all. Tom and you would get married so that they would free your sister. As much as you wanted to believe that the Gaunts were trustworthy, there had been a nasty sting in your stomach ever since the engagement. Would they really give up, even when they had won? They wouldn't be able to control you anymore afterwards, or Tom, or anyone but themselves. Marvolo's filthy grin appeared in your head. Would he ever give it a rest?

"He will free her, won't he?" you asked.

Tom looked into your eyes for a moment, then cleared his throat. "Well, it's what they agreed on."

"But?" you asked.

"But," he went on, "You've seen how they are."

An invisible weight seemed to pull on your limbs and the sting in your stomach got more intense.

"They'll never let go," you breathed. "But how-"

Tom shook his head and exhaled slowly. "I have to show you something."

He gave you the Potions book and opened it at the page where he had put his finger before. "I thought you'd come across it on your own, but as I noticed you wouldn't... Just see for yourself."

You stared at him for a moment, wondering what Morfin's book had to do with anything, before looking down at it. Tom pointed at a recipe, written in scrawled handwriting:

The dust is used to be scattered over an item and will cling to the first person that touches it.

Vanishes the second the victim comes in contact, which makes it very hard to be detected and cured.

Victims will suffer from a distinctively harsh cough, as well as pain and flu-like symptoms, which will worsen each day, until they become fatal. Average time until death is around three weeks after the first encounter with Mors Grano. In most cases, the victim will lose their life before the appropriate antidote can be given.

You didn't bother reading the list of ingredients, as your hands were shaking far too much to even detect another word. You had heard of Mors Grano before. Professor Dippet had brought it up in History of Magic when you had learned about the Passing of Men in 1760. Hundreds of witches had poisoned their abusive husbands with it when the dust had been invented. It had taken years to figure out what had caused such an increased amount of deaths, which happened to involve male wizards only. The potion and most of its ingredients got banned afterwards and you had never heard of another case since.

Until now. It suddenly all made sense. The Gaunts had sent the letter and had coated it with Mors Grano. They had known how to cure Elsie all along and had patiently waited, days and weeks, had let your sister suffer until Father had contacted them. No wonder the owl had given the letter to her, even though it had been addressed to Father. They had specifically chosen her. A ten year old, innocent, little girl.

You weren't sure if you had to throw up, or just needed to punch something really hard, but your stomach did twists and turns that you had never felt before. A thin layer of sweat had formed on your forehead and your hands were still shaking.

"They..." you whispered. "And you knew?"

Tom swallowed thickly. "I didn't at first. But then I came across it when Morfin prepared the poison."

"And you never told me?" you asked, your voice loud and on the verge of breaking, while you attempted to get up from the couch.

"Let me explain," Tom said and grabbed your hand. "Sit down."

"What is there to explain?" you asked, trying to pull away from his grip. "You've known for months. Even before your first visit. Before Elsie got sick. And you never tried to prevent it, nor did you tell me."

Tom's grip around your hand got tighter the more you tried to get him off you. "I said let me explain. I let you explain yourself when I saw you with Avery, didn't I? Imagine I just ran away then. Now sit down."

Finally, Tom's grip loosened, allowing you to tear your hand away from him. Not knowing what to think or say, you sat down but couldn't bring yourself to even look in his direction.

"Yes, I knew," he began with a sigh. "And I didn't care until I found out what they wanted to use the potion for. But I couldn't tell you. Or anyone. I still can't. I'm unable to talk about it. They were a step ahead. Understand?"

The Gaunts were a step ahead. They always wanted to be. Just like on Christmas Day, when they wanted you and Tom to do-

"An unbreakable vow?" you asked with wide eyes. "You had to vow not to tell anyone."

He nodded. "I vowed not to tell. But I didn't vow not to show."

He turned one page inside the book and handed it to you again.

Ingredients:

The skin of a snake

2 fresh Foxgloves

3 blossoms of a Moly

4 drops of Moondew

5 tears of a Banshee

"The antidote," you mumbled. "Full with an ingredient list and instructions. Morfin brewed it already then? They gave it to Elsie, otherwise, she wouldn't have gotten better."

"He didn't complete it," Tom answered, apparently trying not to say something that would interfere with the vow.

"He left out something? They gave her an unfinished antidote?"

Tom nodded.

"The tears?" you guessed, solely because it was the most powerful and rare item on the list.

"I'm not sure. They never let me into his chamber after the engagement."

"Can we... Can we steal it from him? And add the last ingredient?"

"Marvolo has the flask on him at all times. He's suspicious, even of Morfin."

Bloody hell. Marvolo's paranoia was a real pain. You scanned the antidote again, thinking of all the ways you could get your hands on that potion.

"But I could brew it myself. Most of the ingredients are easy to find. Foxgloves are for sale in Diagon Alley, I've seen them countless times. The Moly, we have it here," you listed and looked at it standing on the desk, finally realising why Tom had tried to keep it alive so badly. "Snakeskin from Nagini. We just wait for her to shed. Moondew and the Banshee tears will be tricky, however."

Tom nodded at every new thing you had said. "You figured it out."

Your stomach had stopped squirming at the glimmer of hope you had for saving Elsie. You carefully read the recipe for the antidote again, understanding how long it would take and how hard it would be to get the potion right. If everything went well, it would be finished mid to late June at the earliest. Besides, Slughorn had never taught you such advanced techniques.

Now that you were thinking of your Professor, it began to dawn on you. "Do you think Slughorn has Moondew and Banshee tears in his chamber?"

"Possibly," Tom answered. "But do you really want to steal from him after what Avery and Lestrange did? I'm sure he's got it all locked up in his office now."

"Well, I have to try. Where else would I get those things from? And I better try soon. The antidote will take months to make as it is and the earlier I start, the better."

Tom took the book, got up from the couch and put it into the drawer of his desk, closing it shut slowly.

"What are you doing?" you asked.

"We're going to Slughorn then, aren't we? Come on."

You followed him out hastily, trying to sort out your thoughts. Frankly, you had not expected to get the ingredients this quickly.

"Wait, how are we going to do it?" you asked, struggling to keep pace. "We can't just sneak in and grab the things we need. He might be in there."

"Even better then," Tom said, not deigning to look at the other students strolling along the hallways. "I talk, you get the stuff."

As Slughorn's office was located on the sixth floor, it took some time to get there. Your mind was still racing around the facts you had just been given and you needed to talk about it.

"I can't believe they made you vow," you muttered. "Marvolo and Morfin are..."

"Bastards," he finished your sentence when you stepped from one of the moving staircases to another. "I'm aware."

"Well, yes they are."

You were the only people on the staircase, floating higher up towards your destination. Tom looked over his shoulder to double-check if anyone could hear him.

"You know what," he said pensively. "I actually expected people to ask me what I, or my family, had done to make the engagement happen. Seeing as it was them who got the ball rolling. But everyone suspected you. They all thought your parents bribed us."

You thought about what to answer for a moment. A sour smile had formed on your face. One that, for all you knew, every woman had worn at least once in her life.

"A woman's intentions will always be questioned a hundred times harsher than those of a man, Tom. What else is new?"

He pressed his lips together, nodded and kept quiet until you reached the sixth floor.

"Wait," you said and got a hold of his hand when you had entered the corridor of Slughorn's office. "I wanted to thank you. For helping me. The book, the Moly and now this. You know you don't have to."

He squeezed your fingers lightly in response.

"Trust me, no one hates Marvolo and Morfin more than I do. If I can make their lives a bit harder, I'll gladly do it. And besides, I want to see your sister become Quidditch captain one day. That will really piss them off."

There wasn't a lot of time to take in Tom's words, as you had arrived. There it was. The door to Slughorn's room.

"Get behind me," Tom ordered. "Make sure he doesn't see you."

You did as he said, pressed your back against the stone wall and watched from a small distance how Tom knocked on the door and Slughorn opened it.

"Oh, Tom," the Professor said. "Good afternoon. What brings you here?"

"Good afternoon Professor. I hope I'm not disturbing you. I have some questions about Avery and Lestrange. I'm trying to sort out some things for Professor Dippet. Would you mind letting me in?"

Slughorn opened the door fully and stepped back. "Of course, boy, of course. Come in."

Tom had left the door open for you to slip in behind them, which you instantly did. He lured Slughorn to the far end of his office, walking backwards and keeping an eye on you. Slughorn's potion stock was right next to the entrance, where you knelt down between the shelves, in case he would turn around unexpectedly.

The small drawers weren't tagged, but you noticed that their contents were sorted alphabetically. As you silently roamed through them, you could hear Tom and Slughorn speak.

"So, Professor," Tom said. "Do you know if Avery and Lestrange have taken anything else? Apart from the Polyjuice Potion?"

The Professor hummed. "Not that I'm aware of, no. Why?"

Every single one of the drawers was filled to the brim with ingredients, some vials even had completed potions in it, but you still hadn't seen the things you were looking for. It was a delicate act to go through everything so quickly, while being quiet at the same time and making sure not to miss anything.

"Well, there were some items found. Residues of Moondew and Banshee tears," Tom explained.

"Banshee tears?" Slughorn asked.

"Yes. We can't be sure if it was them, but I thought if you missed those things from your supply, the two might have something to do with it."

"No, everything else is there, I counted it myself," Slughorn assured. "What baffles me are the Banshee tears."

Tom was an excellent liar, even though Slughorn would have probably bought anything his favourite student said. The bottom drawer at the penultimate row was stuck. You pulled the handle tightly but it only opened up an inch and gave a screech while it did, making you freeze from fear.

"Did you hear something?" Slughorn asked, his voice echoing your way.

"No, I didn't," Tom answered and coughed. "Why are you surprised about the Banshee tears, sir?"

"Well, those tears are rare," the teacher answered, his head directed towards Tom again. "Very rare and also not very legal, boy. I've never seen them anywhere in my whole life. They couldn't have been from me."

No Banshee tears from Slughorn then. You pulled out your wand and cast a nonverbal spell to loosen up the stuck drawer. Should have done that right away, you thought to yourself. Eventually, it opened smoothly and your eyes went over all the flasks and their name tags. Mollowsweed, mandrake, maw, mistletoe berry... Moondew. Thank Merlin! There were over ten vials of it in the drawer, so you hastily took out one and put it into your pocket.

You peeked over the counter, locked eyes with Tom, and pointed towards the door to let him know you would leave.

"I see," Tom went on, his eyes back on Slughorn. "We'll have to look into that. Anyway, if you do notice some Moondew missing, against all expectations, I'm going to have another talk with Dippet about Avery and Lestrange."

"I'll let you know, boy. Thank you."

"Enjoy your evening, sir."