"Minnie!" Severus heard Black cry, and wondered how the man hadn't been slaughtered already. To his shock Minerva merely huffed. He could imagine the affectionate eye roll that accompanied it. Minerva stepped inside, and Black looked startled.
"Snape." Black said, eyes flicking between the two of them. "Please, come in."
"Black." Severus replied, barely keeping the disdain from his voice. If Black could be civilized, well, so could he.
He stiffly seated himself in the parlour of Grimmauld Place, and sat in silence while Minerva and Black exchanged pleasantries. Eventually, they got to the point.
"You're not just here for a social visit." Black observed.
"Obviously." Severus replied, biting back further vitriol. Black grimaced.
"It's about that howler, isn't it?" Black shook his head. "I must admit… I wasn't thinking clearly when I sent it."
"That is quite evident... Well? Out with it! What dangerous item had Harry encountered?" Minerva demanded. Black, for the first time in his entire life, looked entirely serious. Severus was well aware of the irony. He contemplated the both of them, his eyes narrowed as they settled upon Severus.
"Would you both be willing to take a vow not to wilfully disclose this information to another person without my permission?" Black asked. Severus raised a brow, but agreed. Black had been a formidable Auror, even in his youth, loathe as Severus was to admit it. He wouldn't ask such lightly.
Once they had taken their vow, Black exited the room, and returned with a safe. He tapped it, muttering a password, then dripped blood onto it before it opened; a decidedly dark ward that Severus was reluctantly impressed by. From within Black withdrew an innocuous black book.
"This is the diary of Tom Marvelo Riddle… and I also believe it to be his horcrux." Minerva paled, but Severus merely frowned. He'd heard of neither.
"Well?" He hissed, when the both looked at him.
"Tom Marvelo Riddle… that's a name I've not heard in a long while." Minerva said quietly. "I suppose it is likely easier to show you…" She traced the name in the air, so that the letters were burning as she wrote them.
TOM MARVELO RIDDLE
Then, with a flick, the letters began to move, rearranging themselves.
I AM LORD VOLDEMORT
Severus recoiled, looking at the diary in horror.
"The Dark Lord's diary." He whispered.
"It gets worse." Black said. "A horcrux is a dark object that contains a piece of its owner's soul, torn apart through murder." Silver eyes met his own. "In theory, even if the body were destroyed, the soul would live on."
Severus wanted to flee, to leave the room, to storm back to Hogwarts and lock himself away. He didn't want to be in the same country as part of the Dark Lord's soul, let alone the same room.
"You may be interested to know that the last time the Chamber of Secrets was opened, Tom Riddle was a student at Hogwarts."
"You're not saying…" Minerva said, covering her mouth with her shaking hand. "This diary… is responsible?" Black nodded.
"A horcrux is a piece of human soul. It wants a body, to be let free. It was likely possessing a child. I suppose we're lucky that Harry found it." Severus snorted.
"Luck! Luck has nothing to do with it! That boy is a magnet for trouble." Black glared at him. "Don't give me that look! You know it's true!" Black sighed, looking his age.
"You're right, of course. Only Harry would find a part of You Know Who's soul and send it to me in the post." Black huffed a laugh.
"If that is what is keeping him alive, then why haven't you destroyed it?" Minerva exclaimed, having recovered from her shock. Black grimaced.
"I've tried! Nothing I can do will destroy it. I've tried to burn it, to tear it apart, curse it! Nothing!" Black lamented. Severus eyed the diary. It sat on the table, mocking him in its innocent appearance.
"I have an idea." Severus said, even as he shied away from it.
"Do tell." Black growled. Severus ignored him.
"Is there somewhere any backlash can be contained?" He asked instead. Black huffed, but led him to a ritual room.
"Stay back." Severus warned them. He looked at the diary, and thought of his pain when he had learned Lily was to die, the feeling of betrayal, of hatred toward his former master, his utter loathing of the Dark Lord. His hands shook as he raised his wand.
"Avada Kedavra!" The room was lit up in a flash of green light. The diary hissed where the curse struck it, and black smoke poured out, writhing and screaming, before doubling in on itself.
BANG. The diary exploded, throwing him into the wall. His vision blurred, and spots of light swam before his eyes. His ears were ringing as he scrambled to his feet, and stalked over to the remains of the diary. It was just burnt paper and ash. He kicked it, and the remains disintegrated.
"Done." He muttered, pushing past Black. He couldn't bear to look at Minerva, not now.
"Severus." She called out. He spun to face her, glaring at her shoes. She placed a hand upon his arm. "Well done." She said quietly. He glanced up, but none of the revulsion he imagined was in her face, just sadness. He nodded sharply, and stalked out the house. He needed a firewhiskey.
"Master master master master." Harry groaned and rolled over in his bed. He was back in school for the spring term, unfortunately. It was also the middle of the night.
"What is it Baneofallrodents? I'm trying to sleep."
"Master! I have found the King Snake."
"What?" Harry grumbled
"There is another snake, the King Snake."
"The King Snake?" Harry rolled over. "Not now." He hissed, and fell back to sleep.