He eyes the sod venomously, glaring at him with poison-laced daggers. The rat cowers on the floor, completely at his mercy. Both of them are in a holding cell where the Dark Lord imprisoned the rat for disobeying his orders to kill a Muggle. It has been four years since he learned who the real traitor to the Potters was, and the attacker is now itching to get his proper revenge.
"So, Wormtail," he gives as his preamble, starting to circle the rat ever so slowly. He speaks deliberately, enunciating every word he utters. "I've waited for four years to exact my vengeance, and here we are. Pity you didn't foresee the consequences of betraying the side of the Light before you dishonorably betrayed them. Please, do feel free to correct me if I am mistaken," he adds coldly, knowing that the rat would be too cowardly to speak against him.
"At first, I had vowed to kill your friend for what happened, for everyone believed that you were dead. Well, we all know who the real disgusting, filthy, traitorous coward is, don't we? Tell me, Wormtail. What...punishment...do you think I should administer? Hmm? Should it be magical, or maybe...Muggle? I've heard of their...corporal...ways of dealing with traitors. But a good beating just simply won't do, will it? Oh, yes, Wormtail," he sneers, savoring his every threat, "I think you deserve much, much worse."
At this, the rat flinches.
"You really are the coward, aren't you?" he jabs. "I'd have expected...better...from a follower of the Dark Lord and a rat who is about to...what's the word? I seem to be forgetting." He pauses for a moment, pretending to think of what he already knows. "Ah, yes," he says finally. "Die."
The rat starts crawling back.
"You've nowhere to go, rat. Why bother? Not like you'll be here any longer, am I right?" he asks menacingly.
The filth's Adam's apple bobs up and down. He notices a sheen of sweat covering the coward's forehead. At this, he just laughs.
"At least you possess the grace to sweat, you filthy sod." He pretends to examine the rat's face more closely. He prods it with his wand, pushing hard enough for the skin to break and for the blood to start trickling. "Oh, Wormtail. I'm going to have...fun with you."
At this, the coward starts shaking even more.
He just sneers and says flatly, "Accio Wormtail's wand."
The filth's wand flies from his pocket into the attacker's other hand. He pockets his own wand, and he waves the rat's wand tauntingly in front of his face.
"I don't believe you'll be needing this any longer." With that, he snaps the filth's wand and carelessly throws the pieces to one side. He watches as he crawls pathetically to that side, picks up the pieces in his hands, and starts trembling. The attacker laughs again, cruelly this time.
"Y-you," the rat squeaks out, "a-are a monster—"
"Enough!" The attacker's eyes narrow. "That's rich, coming from you," he spits. Suddenly, his face is demented. Inhuman. Ravaged. Suddenly, all that can be seen is the raw pain and anguish which has cursed him for almost two decades.
"You're the one who was cowardly enough to betray her to the Dark Lord. Not me. You know what I did once I realized she was in danger."
Not wanting to wait any longer, he points his wand at the rat. "Crucio," he whispers.
The rat lets out an ear-piercing shriek. His back arches and he convulses erratically. He twists and turns, trying to stifle the pain to no avail. The rat glances at the attacker. His eyes are glittering with cruelty. There's a harsh anger about them. They show no sign of any control, an intent to unleash his full wrath upon the cowardly man who caused the death of the woman he loved.
He strengthens the curse, relishing the screams he hears from the rat. He feeds off of the traitor's pain and anguish, and he lives off of revenge. Flashes appear in his mind: images of Wormtail's bloodied, mutilated corpse with his brains blasted open; these images are the motivation he possesses to continue to put the rat through this utter agony in such a heartless way.
"Do you know how long I have wanted to do this?" he hisses, speaking amidst the screams as if they were having a civil conversation over a cup of tea. Of course, no answer is given, and he goes on.
"Your handling of the Cruciatus is pathetic," he says bluntly. "I've handled much worse at the hands of the Dark Lord himself." Suddenly, he cancels the curse, and the rat is left shaking uncontrollably.
"You're lucky that I'm not as...insane...as dear Bella. She'd have broken every bone in your body at this point. I only administered the Cruciatus to teach you a lesson. Everything I do has a purpose. I'd like to think of myself as one of the...sane Death Eaters."
"Silencio!" he shouts, pointing his wand at the rat. Immediately, the rat silences. He doesn't need to hear the coward's useless blabber.
"Why do you think you're here? Even your sorry excuse of a brain should be able to figure that out." The attacker clicks his tongue while shaking his head. "Cowardly and incompetent. Honestly, I don't know how the Dark Lord even accepted you into his ranks in the first place. I know he has...standards."
He points his wand at the rat again and says, "Spina confractus ossa."
Sickening crunches can be heard reverberating throughout the room. He smiles wickedly. "Now, you cannot stand," he says softly.
"Frange sinistra brachium ossa." More sickening crunches. "Now, you cannot summon the Dark Lord even if you tried." He walks over to the literally broken rat and carelessly pulls the rat's left arm sleeve. He notices how the sod's eyes widen and how his eyes leak miserable tears. He finds the Dark Mark and places his boot on it. Then, he raises his foot slowly, aiming it for Wormtail's left forearm, calculating his blow—
His foot slams into the Dark Mark, and he grinds that area until it's but a pile of mush. Wormtail's screams grow to be more and more pathetic than the last. Apparently, the Silencing Charm has worn off. Soon, it sounds like nails being dragged on a chalkboard, and he can't take it anymore. He lifts up his boot. With a flick of his wand, he mutters, "Scourgify," and his boot is immediately cleaned of the blood, flesh, and bone that had stuck to the boot as Wormtail's hand was crushed; it is satisfying, this revenge. He points his wand at Wormtail's heart.
"Subsisto cordis pulsatio." Wormtail clutches his chest with the hand he has left and starts wheezing. The attacker just smiles.
"You're having what the Muggles call a 'heart attack'," he whispers, his words as soft as a feather but as sharp as a blade. "To finish the job, let me bring one of my own creations out to play, shall we?"
The tears say it all.
"Sectumsempra." The filth's body slackens, and even the tears he sheds aren't enough to cope with the apparent pain. Blood starts leaking from his arms, legs, chest, and neck. The attacker just stands there and watches the rat suffer.
"You'll die soon of blood loss, I gather. Pity that you didn't foresee the consequences of joining the Dark Lord before it came to this." The filth starts silently sobbing.
"But don't worry, Wormtail," he adds with fake concern. "It won't last for long. Soon, the world will be rid of you, and everyone will be safe from your wavering loyalties once more."
Long moments pass, and soon, Wormtail is all but a squalid, bloody mess on the floor. The attacker chuckles, knowing that the rat absolutely did get what he deserved. He removes the Muffliato Charm and the wards he had set when he entered the godforsaken room. He starts making his way to the cell door to report back to his master, but pauses and looks at Wormtail for the last time.
"I may be reformed," he says tonelessly to the body, "but I'm always a Death Eater. Even when I'm not."
And it would always be true, for if there is one thing that distinguishes him from his allies, it's this simple fact:
Severus Snape shows no mercy. Ever.