Wormtail,

I can't help but wonder why I'm writing to you, of all people. The letter I write now will never be sent, it will never travel outside these walls and it will probably be destroyed by the Dementors after they discover that I'm gone.

I've spent nearly thirteen years in prison for your crime. And in that time, I haven't gone insane. Maybe that's why I'm writing to you, to prove that Azkaban hasn't worked on me. I can take some silent satisfaction from that.

You guessed that someone would come for you, one day. You knew that your attempt at life with a wizarding family wouldn't last forever. But as soon as I saw you in the Daily Prophet, I wasn't going to let you return to Hogwarts, where Harry would be. I might have missed out on over a decade of my godson's life but a fire was kindled inside me as soon as I realised that you would have access to Harry Potter. Four words, Wormtail, four words. OVER MY DEAD BODY. And I'm not dead yet, far from it. In fact, I'm alive enough to stop you. I didn't stop you killing Lily and James all those years ago but there's no chance in hell that you'll ever get the opportunity to harm Harry. I doubt that you'd dare to, but from what I hear these days, Voldemort won't be gone for good. When he's back, he won't have a ready-made servant positioned beside Harry. It's all going to end now, one way or another.

When I think about what you did, I feel anger, as much anger as I can possibly feel in a place where emotions are so reduced to self-pity and depression. I used to feel sorrow, an intense sense of betrayal, guilt and sadness because I'd lost all of my best friends. It took me years to come to terms with the fact that another Marauder had betrayed us all. One of our own. You knew that James's death would absolutely destroy me, from the inside out. You knew that it would tear all of our lives apart and some twisted little part of you could justify that. I've never understood your mind, Wormtail. Out of the four of us, I knew the least about you. Moony was introverted, without a doubt but it took friends like us to penetrate the walls he had built around himself. Once we had proven our loyalty to him, he was a changed man. Moony trusted us. I thought I'd always trust him. I knew him well, I could always predict what he'd do. Prongs, Prongs and I were like brothers. No, we were brothers. I understood everything about him and he knew me just as well. There was nothing about each other that we didn't know. Nothing. I realise now that I knew him better than I ever knew myself.

You saw all of this. You must have seen that the three of us had a connection that you didn't. A connection that you never even sought. I always wondered why you were the odd one out but twelve years ago, I realised why. It was a lie all along. It was never about loyalty or brotherhood or support or bravery with you. It was about protection. You gave yourself to the highest bidder. At Hogwarts, we were the cool kids, the elite gang of pranksters who everyone secretly admired. We were vain. Arrogant. Nothing could touch us, or our friends. So you aligned yourself with us. We kept you safe from bullies. We stopped you failing all of your subjects even though you struggled with the most basic spells. We saved you from seven years of loneliness, from the fear of never making connections with a group. You had all you'd ever wanted- three friends who'd go to the ends of the Earth and beyond to help you.

But outside Hogwarts, one day you must have realised. The truth must suddenly have hit you. You must have felt as alone as you did on the Hogwarts Express when you sat in a carriage by yourself for the entire journey, until one Remus Lupin came looking for somewhere quiet to read his spellbook, started conversing with you and finally introduced you to James and I. When we left school, we weren't the highest bidder anymore and that scared you to the core. We came into a world of war, of death and of hate. There were wizards far more powerful than us and when they called to you, it took very little to send you running for their protection instead of ours. Theirs meant more now. It was stronger than what we could offer. And when you realised that it meant betraying your old friends, you exchanged our lives for yours in a rat's heartbeat.

Voldemort gave you the chance to prove your worth. With us, you'd always considered yourself inferior. We never saw you as the spineless, weak, talentless little thing that you turned out to be but you saw it in yourself and then allowed it to take over you. You jumped at the chance to do something big, to make Voldemort see how much of a valuable player you were. Then, you could be sure that you'd earned his protection this time. You could take your place amongst the big boys.

But that wasn't how it worked with the Death Eaters, was it Wormtail? Voldemort was harsh, cruel and irrational. When you handed him the Potters, when you betrayed your best friends for him, you expected to be honoured beyond your dreams for the act. It all fell apart when Voldemort was destroyed. You knew that you would be blamed by the other Death Eaters. They didn't care enough to look after you. They never had.

So you framed me, faked your death, sent me to Azkaban, condemned Moony to a life of solitude and you ran away, again. You went to find someone new to protect you.

And why, for your entire life, has your single goal been to seek protection and security above all else? I'll tell you why, Wormtail. Because you're a coward and you always will be. You had seven years to change that but when it came to choosing between loyalty and friendship or protection and power, you chose the latter. You chose wrong, and what's more, you knew it.

Don't ever think that I'm condoning what you did just because I can comprehend why you did it. I spent the best part of twelve years racking my brains, trying to work out where we all went wrong and it all came down to you. We were all wrong about you. I've seen you in moments of bravery and you had the potential to shine for Gryffindor, like we all did. The first time Moony transformed, we were terrified that our Animagi would only aggravate him further. You scurried down to the knot at the foot of the Whomping Willow and pressed it, without hesitation. When Prongs and I saw you, we followed. There were flashes of bravery in your past but ultimately, you will always be remembered by the Marauders as a coward because you weren't strong enough to choose the right path over the wrong one when it really mattered.

I don't feel sorry for you. I hate you now. I've come to terms with what you did but I'll never rest until I've avenged my best friend and his wife. It was due to my suggestion that they chose you as Secret Keeper. I thought that no one would ever suspect you and in a twisted way, I was right. We didn't even suspect you. I didn't trust Moony, something I will always regret until the day I die. You were far too quick to accept my doubts about him. I never even had concrete reasons for my sudden disbelief in him, I just feared that out of everyone, after everything that he'd been through, he'd be more susceptible to cracking under the pressure. But I knew Moony, better than I knew you. He would never have betrayed us. It would have proven that we were wrong about him and it would have confirmed that he really was the monster that he dreaded. Had I been sensible and rational to sit down and work it out, I might have come to the right conclusion. Fortunately for you and unfortunately for the rest of us, I'm not a rational, calm person. I was rash, hasty and driven by my emotions, even more so then than I am now.

In writing this, I still can't work out why my brain decided to address this to you instead of Remus, Dumbledore or even Harry. I just wanted to reiterate what exactly your betrayal meant to us. I want to assure you that nothing you ever say will be able to justify what you did. No matter how much they tortured you or threatened you with death, you should not have backed down. Had you died, you would have died as big a hero as I imagine that the world believes you actually are. We would have cried for you, mourned for you and we would never have forgotten the sacrifices you made which saved our lives. And even though you would have been dead, we would have known that you loved us and that you honoured the Marauders even in your final moments of life. You could have had all of that, even if they did kill you. Had you confided in us, we would have protected you. I can't even imagine wanting to protect you now. If I had you in front of me at this moment, I'd attack you with every ounce of strength that I have left. Even if it killed me too.

I know that the Death Eaters didn't torture you to force you to succumb to them. You would never have let it get that far, I see that now. I used to make fun of you at school but I always believed, in my heart, that when the time came, you'd be brave when it mattered. You'd show us all why you were a Gryffindor. To this day, I still can't work that one out and I've had more thinking time than most.

In the end it was all about saving your own neck. I should have realised when your Animagus was a rat. It reflected your true colours. Prongs was a stag, majestic and brave until the end, like always. I transform into a dog and like to think that the 'man's best friend' connected to dogs is something which reflects me. I was always as good a friend as I could be. Not to Remus in the end but to James. Although I inadvertently enabled you to betray him, I only ever intended to protect him.

You're a rat, Wormtail. You sneak, you're sly, you're cleverer than people give you credit for. I imagined, putting myself in your shoes, that you'd find a wizarding family to take you in and keep an ear out for my death, my escape or Voldemort's return. When I saw you in the Daily Prophet, I saw that I'd been right about you again. Shame that I was wrong the one time that it really mattered.

You tore my life into shreds. You're the reason that the best friend that I ever had is dead. You're the reason that Moony, who used to be one of my closest friends, believes me to be guilty of betrayal and murder. After all, what else could he think? He would never guess that you were the traitor instead of me. He thought that I was Secret Keeper. Moony is logical, if nothing else. If I was Secret Keeper, I would have been the only one able to reveal Lily and James's whereabouts to Voldemort. I hate you because Moony hates me and he's somewhere I can't reach to tell him he's wrong. You really did ruin my life, in every single way possible.

More than I ever believed that anyone would be capable of.

I used to be so carefree, so trusting. Now I'm suspicious and more logical, less rash.

I'm less human because of you, Wormtail.

There's nothing else I need to say. I will never forgive you, only because after all I've learnt about you, I know in my heart that you never will be genuinely sorry. If you could go back in time, you'd do the same again, wouldn't you? You're too much of a coward to die for your friends, no matter how much we used to mean to you. Even when you know the consequences, it's still all about you. Even after you let Voldemort murder Prongs, you didn't have enough guilt or sorrow to let me have my revenge. You had to frame me. You had to escape to save yourself once again. It was always about you, always about what you could gain, how you could benefit.

Let me tell you one more thing, Wormtail. Voldemort will NEVER love you like we did. No one will ever care about you or protect you again.

You're on your own now. Does that scare you?

Watch out for the dog and the wolf. We'll always be on your little ratty tail.

Padfoot

THREE YEARS LATER

"Wormtail," Bellatrix sidled towards me nastily. I felt my insides go cold. "I've got something for you. Found it in one of the cells before we left. It's addressed to you."

I couldn't speak. I shook my head.

"I don't want to read it," I stammered but Bellatrix was one step ahead of me.

"I'll read it to you, Wormy," she hissed in my face. My eyes widened. My heart skipped vital beats.

"NO!" I almost shouted, half-sobbing. "I...I can read it myself." She snatched the letter away from me a few times, teasing, mocking. Eventually I grabbed the corner of it. It was written on the back page of the Daily Prophet. One glance at the writing told me that it was from him. Slipping away from Bellatrix's gaze, I began to read.

When I'd finished, I wanted to cry. Oh Merlin, Sirius really did hate me. He would have killed me shortly after that, if it wasn't for Harry. If it wasn't for James's son. The son who, because of me, might be dead very soon.

"Your Animagus was a rat...it reflected your true colours…" I wanted to cry until I had no tears left. I really did.

"You're a coward and you always will be…" The worst part was that I had no defence to anything that Sirius had told me. Every single word was the truth. He saw through my pitiful tears, my apologies. I hated what I was but knowing that Sirius knew all of those things too? Knowing that he hated me because of them, because of what I'd done? It was the worst torture.

Bellatrix sniggered over my shoulder.

"Poor Wormy," she mocked. "What can I say? That malicious temper clearly runs in the family." I wanted to scream at her. I wanted to tell her that someone like Sirius didn't deserve to have evil like her tainting his name. But I wasn't brave enough. As usual. Bellatrix began to laugh, a cold and heartless laugh.

"You know what makes me happy?" she asked.

"No," I whispered wretchedly, although I did. Killing.

"You really don't know!" she cried triumphantly. I shook my head stupidly. Bellatrix put her face close to mine.

"I killed Sirius Black in the fight a few days ago."

My face must have fuelled her laughter and she roared manically as I stood, rigid.

Sirius was dead.

Dead… the woman in front of me had killed Sirius and I knew I wouldn't even consider avenging him. Oh Merlin...he'd never forgiven me. He never would. Too many of my friends had died hating me. That vicious letter was the last I would ever hear from him. I couldn't help but burst into tears. Bellatrix had killed him. Padfoot was gone forever.

He was right again though. I was on my own now, even more so than ever before. My old friends were either dead or they hated me. Or both. Any prayers of reconciliation would never be answered.

I let the tears pour as Bellatrix turned her wand on me.

"HOW DARE YOU CRY FOR A BLOOD-TRAITOR LIKE THAT?" I sobbed even harder, for Sirius, for the war, for my lost friends. But mostly for myself.

"CRUCIO!" Bellatrix screeched and I fell flat on my back, twitching in agony.

The rat almost wished that the dog and wolf were on his tail. Even that would have been better than this.