It was two weeks into the term and Harry was back. I can't say I anticipated it but Hogwarts was kinda strange without him around.

Of course my brother knew I had been behind his rescue and he couldn't thank me enough. Apparently Silverspur had picked him up in the Leaky Cauldron where he had made plans to get some of his Gringotts money and fly away before they could take his broom too. The whole process of him being admitted back to Hogwarts had been sped up considerably by the news of Sirius Black escaping Azkaban but Harry didn't know that. Wouldn't have to either. I enjoyed being the hero of the day. The Gryffindors were throwing a party and I was the first snake invited into their tower in what must have been centuries. Of course I declined and I think they were relieved too. They were beyond happy to have their best seeker ever back but Ron was reminding everyone exactly where I had spent my summer and why. Rumors were already starting that I had cooped up with Black in a plot to kill Harry. Completely ignoring that it would have been so much easier for Black to kill Harry at the Dursleys they thought I wanted to have Harry at Hogwarts because that's where Black was heading who couldn't know where to search for him otherwise. As if there wasn't a spell for tracking persons. But well, try to argue with teenies.

Another few weeks went past and soon it was October. After such a good deed I felt it was time for some evil-doing again. That's why I found myself leaning against a pillar down in a less used part of the dungeons waiting for the Weasley twins. They had received a message from me to come here that had been passed through half a dozen hands first. Aside from making sure nobody knew where it came from I just liked to display my power that way. I still waited for them under the invisibility cloak and checked thrice to make sure they were alone before stepping out of the shadows.

"Fred and George Weasley", I whispered, making them jump. They knew of course it was me they were supposed to meet here, they had the Marauders Map after all. I still managed to surprise them a little.

"Before I went to that place", I said without preamble, "you told me I could count on you. You wanted to be in on it when I planned something big. Does your offer still stand?"

The twins exchanged a look. "It does", they said.

"I do have something planned. It's big but it's also... personal. It's likely I'll be the only one affected."

"How big?", the one I decided was Fred asked with gleaming eyes.

"Big enough to put me right back to that place." Nobody was supposed to know I wasn't affected by the dementors so I had to appear as if I didn't even dare to speak the places' name anymore.

The twins blanched. "What the hell would you-"
"-risk that for!?"

"Revenge", I said simply.

Realization dawned on their faces. "You know about Black."

"I need you help."

George nodded grimly. "What can we do for you?"

"I need you to go to your brother Ron and tell him you have a really good idea how he could get back on me for Ginny. In exchange for telling him you ask him to give you his pet rat Scabbers. When he asks, tell him you plan on testing some candy you invented on it."

George shook his head. "I don't really see where this is heading. Why would you want him to get revenge on you?"

"Do not question, George! Did you notice that Professor Lupin is sick really often? Go to Ron and tell him that Lupin is secretly experimenting with some dark creatures that he has to take care of during those days and that he keeps them in his office. He is to drop that information around me, hoping I will go and investigate. Make sure to propose that coming Saturday night would be a really good time to do it since he gets a few new creatures then. That will get me in a potentially life-threatening situation."

"Okay... Wait, is that actually true?"
I shook my head. "Of course not. But once I tell Lupin all about it he will want to expel Ron for that prank. I would have the power to prevent that though. So you offer to give me Scabbers and a bunch of pranking devices in exchange for keeping quiet about it. You save your brothers skin, he's indebted to you and me, severely humiliated and I get to torture his rat, which he can't do anything about because else I rat him out."

"We thought this had something to do with Black."
"Now it seems it doesn't, but-"
"- we can totally understand you wanting revenge on Ron too. Tormenting his pet is kinda creepy..."
"...but we'll take the challenge."

"There is a condition."
"Of course there is."

"As soon as you get the rat you have to put it into a cage made out of unbreakable glass. It has to be a strong cage, as heavily warded as you can get it to prevent Scabbers from getting away or anyone getting him out. Never must anyone find out this was my plan though. Understood?"
The twins mock-saluted. "Yes, Sir! Operation Ratnapping begins!"

"Great. And never forget: Do not question."
"Do not doubt", Fred added with a grin.

"Tell no one", George said gravely. "Understood, boss."

"I do know about Black, by the way, but I don't think Harry does. Don't tell him, at least not yet. Also if you happen to see his name on that handy map of yours, I'd appreciate it if you called me first."
"How do you know about the map!?"
"I happen to know one of its creators. Maybe one day when you're especially useful I'll introduce you. For now I trust you with it. Just don't give it anybody else."

They pouted. "Not fair."

I laughed coldly. "When was life ever fair?"

It was the first Hogsmeade-Weekend. Harry wasn't allowed to go of course and somehow McGonogall and Flitwick decided to go for a walk to the village at just the same time I went with my Slytherin crew. I quickly ordered the nest to provide a distraction and they hold a full blown snowball fight in the middle of the village square. Once the teachers looked the other way I pulled out the invisibility cloak, charmed my shoes not to leave any marks and vanished.

Five minutes later I had made my way to the cave. The cave in which stood a small tend with a big grim-like dog lying in front of it. The dog barked happily and came to greet me. Only when I entered the tent which expanded to hold a whole apartment fully furnished did he change back into a man and hugged me close. I managed to stiff only a little.

"How are you doing, Sirius?", I asked kindly.

"Great!", he beamed, "that little elf of yours is taking good care of me. He brings me food and clothing and stuff. It's been kinda boring actually."

"You'll be more free to move around shortly", I said. "I have opened negotiations with the dementors. As soon as I'm sure they won't hunt you down you can explore the forbidden forest. I want you to find a nice quit place away from curious eyes and ears where we can put our plan into action."

Black gave me a strange look. "Negotiations with the dementors? Did I miss something?"
"You sure did. I can't explain it right now but I'm planning to take action during the next Hogsmeade-Weekend. We will have our revenge soon."
Sirius nodded grimly. "That bastard Dumbledore will pay for what he's done to you." But then his expression changed and he had to look down.

"What is it?", I asked worried.

"It's just... I wonder what Remus will think of me. Will he understand?"
"He doesn't have to know", I whispered. "If everything goes according to plan nobody has to know. If we find Pettigrew maybe you can even step out of the shadows again. We can be a family, you me and Harry."

Sirius smiled sadly. "I would like that very much, Charles."

"Me too. But in order for this to happen Dumbledore has to be removed. He would never allow us to live with you."

The animagus grimaced. "I know that. I don't like it but I'll do it. I'll do it for you, for you and Harry."

Now I was the one to hug him, plastering a great smile on my face. "You have no idea how much that means to me... to finally be free of him..." Did I overdo it a bit? Nah, you can never be childish enough with Sirius.

I pulled back again. "I know you probably won't need it but I still want you to have a wand. There's a room in Hogwarts that stores all the things students have lost over the last thousand years. There have to be a few wands in it. Let's sneak in and get one that fits you."
"A room that stores lost things? I never heard of that one!"
"The marauders didn't find out all of Hogwarts secrets, you know?"
"No way!"

I laughed. "Relax, I already promised you to show you."

I didn't want Black to know about my cloak so I used the disillusionment charm on his animagus form that I had spend the last three weeks to master. After along walk through the tunnel in Honeydukes we got to the Room of Requirement and he picked his wand (or rather, a wand picked him). With that the first part of my plan was complete.

It was Saturday, the day before another full moon and I was on my way back from another set of Outtakes with Lisa and Theodore trailing behind me. On our way Ron Weasley 'accidentally' bumped into us and Theo immediately started to pick a fight. Ron only fought back weakly and always tried to get past him to pick up the books he had dropped.

That made me suspicious immediately, since when did he carry books around? So I looked closer and noticed a piece of parchment that had 'top secret' not-so-discretely written all over it.

"What do we have here?", I leered, miming the perfect bully and picked it up.

"That's mine!", Ron protested and tried to grab it, but Theo shoved him away.

"Really? Now what kind of secret information could you know?" I held the paper up to tease him but didn't read it. "Who would tell you anything of importance anyway?"
"Something you could never find out on yourself!", he spat with a hint of triumph.

"Oh?"
"I know why Lupin is always disappearing and replaced by Snape. He isn't really sick!"

I grinned. "Now you have my attention." I gazed down at the parchment. It only read the current date and a time.

"What does that mean?"

Ron was silent, although it was obvious to me he wanted to tell. I gave Theo a wink and he drew his wand, pointing it at Weasleys throat. "The boss asked you a question, Weasel!"

Weasley tried to look intimated and hide his glee. "Fine! Rumor goes he's experimenting with dark creatures in there and will get a new one today."

"Interesting", I said, seemingly lost in thought. I called the Slytherin back and Ron left not without sneering at me.

"What are you going to do with that information?", Theodore asked curiously.

"The information is false", I stated, "that was plain to see. It's a trap, but a brilliant one."
"How can it be brilliant if it's plain to see?", Lisa asked confused.

"Oh, I'm not talking about this pathetic display just now. I'm talking about the trap I set for him."I chuckled. "This will be so much fun."

I spent the rest fo the day going over the Outtakes lessons planned for the new first year muggleborns together with Hermione. As soon as the sun set I excused myself and returned to the common room. I stayed there reading up on bubble head charms for two more hours before I went to bed. Which means I shut the curtains to my bed and put on the invisibility cloak. I went up to Professor Lupins office and had Notch take away the cloak before working to open the door with one of these knifes that open doors that I found in the Room of Hidden Things. I wasn't good enough at ward-breaking to do it with a spell and Alohomora didn't work.

Carefully I opened the door, slipped in and shut it behind me. Only then did I look ahead. The office was empty. There was a desk at the front with the aquarium for the grindeloh and a wardrobe next to it. Disappointed I thought Lupin wasn't here although he should be, the books had said so...

And then I heard a whimper. I heard the noise of claws scratching over stone. Slowly and careful to be quiet I stepped to the side and circled the desk.

There he was. Professor Lupin was curled up behind the desk on the hard ground in his wolf form. His feet were chained to the desk and bleeding where he had struggled against the restraints. His legs were too long and thin for a wolf and his hands resembled more the paws of a bear then a wolf. But his gray fur was far richer then I had expected. He didn't look like the bald monkey from the movie he looked... well, like a werewolf.

I let my eyes widen in horror and took a step back.

"P-Professor Lupin?!", I said raspy. The wolf looked at me, sniffed at me and I saw his yellow eyes in widen in real terror as opposed to my fake one.

"Oh my god", I choked out, "but Weasley said..." Then I clasped my mouth shut, turned on my heels and fled the office, locking it with every charm I knew.

"Charles Potter? I'd like you to stay for a moment."

My nest didn't dare to even shot me a questioning look as I froze on the spot, my back still turned to the teachers table.

"Charles? Is everything alright?" Of course, Hermione hadn't learned yet when her concern was unappreciated.

"Go ahead", I said with a shaky voice. "I'll see you at potions."

Professor Lupin waited until the room was empty before he sighed deeply. He had been twitchy all day and shooting me worried glances. It was three days since I saw him in his wolf form.

"Charles", he began sadly and it was the first time he called me by my first name, "I think we... I think we need to talk about what you saw in my office."

I remained silent.

"I... I want you to know that this is nothing I have purposefully kept a secret. The headmaster knows of my... condition and so do the other teachers."
"But nobody else does", I whispered.

"No", he admitted. "If the parents knew that... someone like me taught their children, they'd surely demand me to be fired. I also want you to know that I am taking a potion every month that allows me to keep my mind when... when I'm sick." He couldn't even say it out aloud.

"Well, if you hadn't I'd be dead by now", I replied in an attempt to spread false amusement.

Lupin coughed. "Yes, well... Please don't take this the wrong way but I have to know if you've told anyone."
Slowly I shook my head. "No. I think Hermione will figure it out on her own soon though. She's very bright."

"I see. Well... one year was as much as I could hope for anyway. I can understand it if you don't want to... I mean, if you think it's best to tell your guardians I can't stop you..."
"Are you kidding?", I asked with a raised eyebrow. "The Dursleys would probably sent you back some tasty recipes for human flesh. They despise both Harry and me simply for being magical. Also compared to the last two professors in this subject I've learned the most with you, even though a lot of it is useless knowledge about how to defend against rare creatures nobody is likely to ever encounter if they don't travel through the wilderness and not actually defense against the dark arts." I just couldn't resist that jab. "I won't tell anybody about it, Professor. I'll even tell Hermione she can trust you."

A massive weight seems to be lifted off Lupins shoulders.

"I – I don't know what to – thank you, Charles."

I grinned. "Hey, I'm a Slytherin. It's always good to have a Professor on your side. Besides our history Professor is a vampire, our charms Professor half goblin and the Professor for care is half giant. There's really no need for you to worry about not fitting into the picture."

Lupin blinked in surprise. "I... never thought about it like that."
"Really?", I scoffed. "It looks like someone is building up a diplomacy club for magical races. Or just negotiating grounds for forming allegiances for a major war. Hogwarts is more like a fortress then a castle, more like a refugee for politically persecuted then a school for children. More like a death trap then the safest place on the world. Every Slytherin can see that. Then again, who ever listens to Slytherins?"
Lupin appeared stunned for a moment.

I merely shrugged. "Just saying. There's a reason I wanted to stay in the muggle world originally."

The werewolf shook his head. "I have never... ever had any intention of harming a student. But you're right, accidents can never be counted out. That's why I have to know what you were doing in my office in the middle of the night."
I managed to look sheepish. "Well, that was a stupid idea, obviously. I'm not sure if you realize this, Sir, but there are already odd rumors about you around the school. Someone told me you were secretly experimenting on dark creatures during those nights and you were supposed to get a new one this evening so I wanted to take a look..."

Lupins face grew ashen. "Did they... did they specifically tell you it was at this time?"
I nodded hesitantly.

"Who was it?"

"Charles, please, don't you understand? If this person knew about... about me this might've been an attempt to seriously hurt you, maybe even kill you!"

"I... It was just a prank. I don't think he actually meant..." But then I stopped and scowled as if remembering something that contradicted my words.

"Weasley", Lupin said quietly. "That's the name you whispered when you came in here. Tell me Charles, was it Ronald Weasley? I know he blames you for the unfortunate death of his sister..."

My expression darkened.

"Please, Professor, let me resolve this matter on my own."
"Charles... For such a prank... It can go horribly wrong. Right now it might seem innocent, just an accident, but... I once knew a student just like that. We were together at Hogwarts. He told someone if he wanted to know the secret why I kept disappearing he just had to go to a certain place at a certain time and see it for himself. If another student hadn't hauled him back I could have killed that student, I could have bitten him and the one who saved him on top of it. At that time it seemed to be a prank gone wrong but it wasn't, Charles, it wasn't. It was malicious intent."

"I don't know what you mean...", I said hesitantly. I knew exactly what he meant but I wanted him to clarify.

Lupin closed his eyes in pain for a moment. "The student I'm talking about is Sirius Black, Charles. He was friends with your father, Peter Pettigrew and me. He played that really dangerous prank on another student and if your father hadn't saved the victim not only would he have died but I myself would probably have ended kissed by the dementors. Black turned out to be a Death Eater, a traitor and... and he was just a really bad person and if someone is playing such a prank on you you have to tell me!"

But I still remained silent although now I was smiling sadly at him.

"I understand, Professor. I really do. But if you bring that student to justice you'll have to reveal your secret and I'd like for you to stay a little longer. Still it might be a good idea to tell him not to spread such things around..."

Lupin deflated a bit but didn't seem to be overly eager to push the issue either.

"Very well, it that is what you want... If you change your mind, come to me whenever you want."

"I'll make sure to do that", I answered politely before excusing myself.

The next day I met with two tall redheaded boys in the dungeons near the kitchens.

"Do you have it?"

George nodded and pulled out a little cage from his bag. In it sat a brown, sickly looking rat that was chewing on the bars.

"You should've seen Ronnikins face when he came back from his last Defense class", Fred said smugly.
"Looked about to wet himself."
"Lupin asked him to stay behind and whatever he said to him it must've been terrifying because he came to us and begged us to find a way how to appease you."
"We don't know exactly what Lupin said-"
"-although writing to Mum was probably amongst it-"
"-but he only fought very little when we proposed giving Scabbers to you."

I took the cage that wasn't much larger then a mans head and looked at Scabbers closely. He was indeed missing a toe.

"Well done", I congratulated the twins. "You have no idea how much you helped me with this."
"How about as a reward you tell us exactly what Professor Lupins secret is?"
I smirked. "You'll find out soon enough."

"Not fair!"
"Really, boys, you know that the position is cursed, don't you? Every teacher is bound to have his darkest and dirtiest secrets being publicly exposed at the end of the year, leading to him dying, receive some form of permanent damage or at the very least ruin his reputation forever. Since Professor Lupin isn't a Death Eater and actually knows what he's doing with his wand most of the time, it's likely the third option for him, which means you'll find out soon enough. Just be a little patient."

I left the twins to ponder over this and entered my dorm with my new pet. For this very special day I had ordered a special cage. Aside from being unbreakable and impossible to flee from it also had a charm in place that made sure magic could go in but not out. I placed Scabbers in the cage who only fought a little, not knowing what was coming at him. Then I closed the curtains around my bed and pulled out two books. One was about healing charms and one about curses.

"You know, Scabbers", I began, flipping through the books leisurely, "I always found healing arts really interesting. It's not as popular with the other Slytherins but I'd really like to study it. However there's a little problem. How am I supposed to get actual experience on curing a disease that makes your lose all your hair or empty your stomach five times a day? How am I supposed to heal a wound that is bleeding so profusely you might be left unconscious or even die? How am I supposed to break a curse that will turn your skin inside out or switch your organs places all around your body? How am I supposed to do know if my potion will actually save your from a poison that turned your blood into liquid fire? How am I supposed to do any of that if I don't practice beforehand?"

Scabbers had become very silent in his cage and stared at me with wide eyes.

"That's where I need your help, little one. It's all for science, do you understand?" I laughed. "Of course you don't, you're just a rat. Rats don't actually have emotions. I heard they can't even feel pain the same way humans do. Hm, I'm wondering if rats could scream though..."

My face lit up as I supposedly 'found' a particularly interesting spell in the healing book.
"Ah, look! I might need a bit more practice for most of the stuff in here but I'm sure I could try this simple spell." I raised my wand at the rat and it scurried along the walls in fear but the cage was far to small for him to get anywhere or even hide form me.

"Castratus cruenta!"

As it turned out, rats could scream.

Okay, this is getting really mean. Some more preparations in this chapter but in the next, Charles and Sirius will put their plan into action. I've decided not to write all seven years and as such I have to speed things up a bit.

Tell me, who of you is pitiying Scabbers? ;-)