Dudley stared in shock. He had been hoping that Dobby would fetch Dumbledore or McGonagall or Lupin—even Hagrid or Flitwick. Anyone but Snape who he didn't like and, more importantly, didn't trust. He had found out that Snape was a former Death Eater, after all, what if Snape was on Black's side.
Snape had took a moment to take in the scene. His cold black eyes flicked from Dudley and Hermione, to the injured Luna and then to the crumpled form of Black.
"Stand aside, Dursley," Snape said, levelling his wand at Black.
Uncertain, Dudley stepped aside.
"I hoped I would be the one to find you, Black," Snape sneered.
Black stirred, lifting his head up. He looked pale and his lip was bleeding from one of Dudley's punches.
"What are you doing here, Snivellus?" he growled.
"Incarcerous!" Snape snapped, fury in his eyes.
Thick ropes shot out of his wand, binding Black's arms and legs.
"Are you two harmed?" Snape asked, without taking his eyes off Sirius Black.
"No, but Luna …"
"You and Granger will assist her, I will take Black."
Black had started struggling against the ropes binding him as Snape waved his wand, levitating him into the air.
"Sniv … Severus, take me to Dumbledore. As long as that girl brings that rat, I'll come quietly," Black said.
"I don't think there's any reason to trouble the headmaster, Black. Not when the dementors are outside."
"No! Sev …"
"Silencio!" Snape shouted, and Sirius fell silent, his mouth moving wordlessly.
"Professor, you can't! I mean, shouldn't have a trial?" Hermione protested.
"Keep quiet, Granger!" Snape snarled. "You are in enough trouble as it is. Do not make things worse for yourself."
"Azkaban is too good for him," Dudley said, glaring at Black. "After what he's done, he deserves to be thrown to the dementors."
"You don't know the half of it," Snape said.
Dudley lifted Luna into his arms to carry her out. Hermione scooped up Crookshanks to lead the way while Snape levitated Black alongside them.
"Black showed he was quite capable of murder even at Hogwarts, didn't you Black," Snape said softly. "He and his friends tried to play an amusing joke which would have led to my death if James Potter hadn't got cold feet."
Sirius Black struggled more desperately against his bonds.
"Professor, what will happen to him?" Dudley asked,
For the first time since he had entered Hogwarts, Snape actually seemed almost reasonable.
"Did Professor Lupin never educate you about Dementors?" Snape sneered. "That is to be expected. He will receive the Dementor's kiss."
"They'll kiss him?"
"It's where they suck out his soul," Hermione answered. "I read about Dementors when I saw they were at school"
Dudley let out a gasp. "You mean, they kill …"
"Oh no," Snape said. "Much worse than that, isn't it Black? You can survive without a soul, but you will be nothing—no thoughts, no memory, no nothing. Just a husk."
"It sounds horrible," Luna said, through gritted teeth.
"Dementors are the vilest creatures on this planet. Surely you must know what they do by now, Dursley?" said Snape.
"Well … they make me remembers things—the basilisk, in the Chamber of Secrets. And I felt like …"
"… you'd never be happy again," Hermione finished.
"They make you relive your worst memories," Snape said. "And drain your happiness from you. They thrive on misery and despair. Muggles have the concept of hell, as I'm sure you both know—well, if anywhere can be described as hell, it's Azkaban. Most prisoners go mad within days."
"But Black escaped," Hermione said.
"Yes … curiously, Azkaban doesn't work on Black the way it does other prisoners," Snape said, thoughtfully. "Which is why I will hand him to the Dementors now!"
"SEVERUS YOU CAN'T!" Black shouted, frantically. By sheer force of will, he seemed to have broken through Snape's silencing charm. "YOU HAVE TO LISTEN!"
"YOU BETRAYED LILY!" Snape shouted, even louder than Sirius. "IT'S YOUR FAULT SHE'S DEAD!—THROWING YOU TO THE DEMENTORS IS THE LEAST YOU DESERVE. SILENCIO!
Sirius fell silent once more.
Hermione and Dudley did too, almost as if the charm had impacted them as well.
They carried on down the tunnel.
The question that Dudley had was eating away at him. "Professor, by Lily … do you mean my Aunt Lily?"
Snape didn't reply immediately. "I do," he said, after what felt like an age.
"So you knew … you were her friend at Hogwarts?"
"We were friends," Snape said, shortly. "Then this piece of filth betrayed her—led the Dark Lord right to her." His fingers clenched tightly over his wand. "Believe me, Black. It is taking every ounce of self-restraint that I possess not to kill you now."
Dudley glared at Black. Though he had never met his Uncle and Auntie and even though his own parents never spoke of them, they were still his family. And Black had betrayed them to Voldemort—James, Lily and their little boy, Dudley had forgotten his name. Howard, Huge—no, Harry, that was it.
He wondered how things would have been different if Harry had grew up. Maybe they would have been classmates at Hogwarts? He knew James Potter had been a Gryffindor and a member of the Gryffindor quidditch team. If Black hadn't betrayed them, if Voldemort hadn't have murdered them, then perhaps he and Harry Potter would have been friends. Who knows, maybe his mum and Aunt Lily would have made amends. They'd never know, thanks to Black.
They reached the entrance to the tunnel. Crookshanks leapt from Hermione's arms to press the knot on the tree so it was safe.
Dudley stretched as he clambered out with Luna still in her arms. She was pale, her teeth gritted against the pain in her broken leg. It was good to be outside again. It was a cloudy night, the moon and stars were hidden from view.
Hermione and then Snape, still levitating Black alongside them clambered out also.
Suddenly, Dudley was aware of a shuddering, rasping breath and he felt his body grow cold. The Dementors were coming.