The Slytherin dormitories were, despite popular Hogwarts belief, not too bad. Regulus' room was quite quiet, so he could hear the Black Lake through the window, which looked out into the lake- which, thanks to Evans, was now black. Snow was falling outside as November was saying its last goodbyes- not that Regulus could see it.

The beds were dark brown wood and green sheets with silver embroidered into the sheets and the curtains on the beds. Regulus sat on one now, turning the Snitch he had caught earlier in the day over and over in his hands. Barty Crouch Jr had tried to get into the room- but Regulus had locked the door. After persistent knocking, several Alohomora tries (Regulus, despite trying to keep quiet, couldn't help but laugh as Barty thought that would actually work), kicking the door and threatening him half-heartedly, Barty left, and Regulus was glad.

He should have been revising for his NEWTs, but his heart was in his throat, and he couldn't concentrate. He had lent Kreacher to the Dark Lord, and he still hadn't returned.

"What's he making you do, Kreacher?" Regulus whispered to himself, glad all of the other boys were in class, then lunch, then class again, while he was pretending to be ill. "Is he hurting you?"

Crack. Kreacher fell onto the bed, and Regulus jumped. Kreacher began to sob, huddled in a ball.

"Kreacher…" Regulus laid a hand on the shaking elf's back, and the house elf crawled up to him.

"Master Regulus," the elf managed out between sobs. "Master Regulus… Kreacher is sorry, he is so sorry…"

"What did he do, Kreacher?" Regulus whispered. He gave orders in a gentle manner, a manner which could be mistaken for simply asking questions. Sirius, on the other hand, would bark orders, and then wonder why Kreacher didn't like him.

"Kreacher had to drink a potion," Kreacher whispered. "Kreacher saw… terrible things. And the Dark Lord put a locket in a basin… and it filled with the potion again." Kreacher's eyes were filled with tears. "And the Dark Lord l-l-left Kreacher, said he hoped K-Kreacher would d-d-die in the c-cave."

Regulus sat up completely. "He left you there." It was flat. It was cold. Who would do such a thing?

The Dark Lord, obviously. The same person who killed innocent muggles and mudbloods.

But he won't rule forever, Regulus thought, his eyes darting towards his trunk, were stacks of muggle history books. He had researched people like the Dark Lord- mainly Hitler- in the books, his eyes filling with tears at the images of the people in the camps that had been sent up. He didn't have much interest in the 'why's and the 'how's of people's rises to evil- just the fact they had died, and their beliefs were slowly dying out, too.

"He left Kreacher there," Kreacher agreed.

"But… why?" Regulus said. Regulus had spoken so proudly of Kreacher when the Dark Lord had called a meeting and asked for a house-elf.

Kreacher looked up at him, his eyes bloodshot, a tear trembling at the end of his nose.

"Because Kreacher is but a house-elf, Master Regulus," Kreacher said simply. "And the Dark Lord wants a better world than we can offer."

Regulus hugged the house-elf without warning, and the elf began to cry again. Regulus shushed him gently rocking him back and forth.

"A locket, you said he had?" Regulus asked, and Kreacher nodded, still howling. Regulus frowned, and stood up off of the bed. He went looking for his locket, and found it in his trunk, being used as a bookmark for one of the muggle textbooks. He turned it over in his hands.

"Stay here as long as you want, and then go home when you're ready, okay?" Regulus said to Kreacher. "Come back on my birthday- I have to think things over."

Kreacher nodded, his eyes wide. "Where is Master Regulus going, if Kreacher can ask?"

"Kreacher may," Regulus said, picking up his wand. "I'm going to look for some books in Dumbledore's office- he's hidden them away, but I'll find them. I need to do some research, too."

Kreacher nodded, and Regulus left. Dumbledore didn't see Regulus in his office- the old man was asleep- until Regulus was leaving with the books under his robes.

"You look like him, you know."

Regulus turned, his eyes wide. "Excuse me?"

The old man smiled. "The same dark hair… but in more ways than one. But you're different, you know."

Regulus shifted uncomfortably. "You mean Sirius?"

Dumbledore just smiled down at the open book on his desk. "Next time you want to snoop around, Regulus, use an invisibility charm."

"Professor- I-"

"Hurry along now, Regulus." Dumbledore went to add something, but he stopped, his eyes drifting to Regulus' left arm. He gave a sad smile, and Regulus could have sworn he could see tears gathering in his eyes as he looked back down at his book.

For nights on end, he stayed awake until the small hours in the Slytherin Common Room, Barty half asleep in a chair nearby. He gave little grunts whenever Regulus began to speak out loud.

"There's nothing about destroying them," Regulus said one night, his tired eyes skimming the words. "So it must be pretty easy- right?"

Barty grunted, head in his hands. He had no idea what Regulus was talking about- but as Regulus was due to leave Hogwarts at the end of the school year, he was just glad to be spending time with him. November left and December came, bringing a new type of cold November could never hope to achieve.

Regulus continued to do research on horcruxes, each and every book leaving a bitter taste in his mouth. He shuddered at what the Dark Lord had done to achieve his means. The Dark Lord was evil- there was no doubt about it. And the Dark Lord was immortal.

Regulus left Barty the night before his eighteenth birthday to go to his room. Barty was curled up in a ball, his hair mussed and his milky skin creased in a frown. By the light of a patronous he cast- a lion, as he had discovered in third year, soon after Sirius had rescued him from what then was the Glass Lake- he wrote a note. He folded it tightly, and put it in the locket. He wore it around his neck that day, hidden under his robes, reminding him of what he had to do. Barty was confused at why Regulus didn't want to sneak into Hogsmeade. Regulus hadn't been to Hogsmeade since Sirius had left Hogwarts- the place had too many memories of Sirius in it. His laughter echoed down the streets.

He locked himself in the dormitory again, and waited for Kreacher. When he appeared, he was told that Mrs and Mr Black wished him a happy birthday. He gave Regulus three wrapped presents- one from Mrs and Mr Black, one from the extended family, and one badly wrapped one from Kreacher himself. Regulus set them on the bed to open later.

"Thank you, Kreacher," Regulus said. "Tell them I said thank you, too. Could you take me to the cave the Dark Lord took you to?"

Kreacher began to tremble. "Kreacher can."

"Will you?"

Kreacher trembled more. "If you command him to."

Regulus bent down to Kreacher's level. "Kreacher," he said, gently but firmly, a hand on his shoulder. "Take me to the cave, and never breathe a word of it to mother or father… or anyone in the family. Or any Death Eaters. Or the Dark Lord."

Kreacher nodded.

"If Master Regulus gives Kreacher his hand…" Kreacher began to shake like a leaf again. "Kreacher will bring Master Regulus to the cave."

Regulus gave him his hand, and, true to his word, Kreacher brought him to outside a stone wall. Regulus raised an eyebrow.

"There needs to be blood drawn of a human," Kreacher said. "The Dark Lord used a muggle."

"What happened to them?" Regulus asked, getting out his wand.

Kreacher looked at the ground. "The Dark Lord threw them into the lake."

"What lake?"

"You'll see, Master Regulus."

Regulus sighed as he conjured a knife from the air. Muggles' deaths didn't bother him- but the reasons that they died- and the way they died- did. Who would be the last to die?

Hopefully the Dark Lord himself, Regulus thought, and he smiled slightly. He drew the knife across his skin, wincing only slightly. Kreacher covered his eyes as Regulus' blood dropped on the stone.

"It's okay, Kreacher," Regulus whispered. He dropped the knife on the ground as Kreacher led him elsewhere. "I'm fine."

Regulus saw the lake Kreacher had been talking about. But his eyes were fixed on the glowing green basin.

"Is that the potion?" Regulus asked Kreacher, who nodded, slipping his hand into his own. "How do we get to it?"

"There's an invisible chain for a boat- you have to feel around for it," Kreacher said. So, still holding hands with Kreacher, Regulus felt around for the chain, his school robes dipping into the murky waters slightly. He yanked them out, cursing.

Regulus rowed, of course, trying not to look at the pale bodies in the water below. Kreacher sat with his hands over his eyes, not risking anything.

He conjured a goblet out of thin air. I really should have finished that Transfiguration homework, he thought- not that it mattered. It was black on the outside, silver on the inside, with emeralds glistening in the handle. Using his wand, he began to carefully carve his initials on the inside of the goblet.

"Master Regulus?" Kreacher said softly. Regulus nearly dropped the goblet.

"Yes, Kreacher?"

"Do you- do you want Kreacher to drink the potion?" Kreacher looked terrified at the suggestion.

"No!" Regulus explained, half turning around. "No, no." They stood in silence for a while. Regulus loosened the Slytherin tie around his neck, but didn't take it off.

"Does it hurt? Answer me truthfully, Kreacher."

"Yes," Kreacher whispered. "Your worst memories… your stomach burns, your insides burn… and the potion makes up things, makes up lies… I saw…"

"You don't need to tell me," Regulus said quickly, and scooped up some potion in the goblet. "Just… promise me something, okay?"

"Anything, Master Regulus," Kreacher said.

"Make me drink the potion, Kreacher- don't obey any other orders I may give you." Regulus' hand began to shake badly, the potion in the goblet slopping at the edges. "Like I said before, don't breathe a word to any of the family, Death Eaters, or Dark Lord. Once I've drank the potion, switch the lockets." With his free hand, he wrestled the small locket with the note inside from around his neck. "Return home, and destroy the locket."

"What about you, Master Regulus?"

Regulus didn't answer for a good while. "Don't save me."

"Master R-"

"Kreacher! Don't save me, Kreacher- please."

He drank the first cup of potion. Then the second. The third, fourth, fifth. From the sixth onwards, a howling Kreacher had to pour the potion down his screaming throat.

"Kreacher, stop!" Regulus would scream, and Kreacher's tears would mix in with the potion as the house-elf went back and forth, fetching the potion and making him drink it. "Kreacher, please!"

The things he saw… oh, the things he saw. He saw his mother, torturing Sirius, torturing him while Sirius laughed… he saw Kreacher, fully clothed and smiling… he saw his brother again, dressed in his Gryffindor uniform, his arm slung around James' shoulder, claiming James was his only brother… he saw himself on the floor, screaming and howling while other Death Eaters used the newest recruitment for crucio practise… and he saw the Dark Lord last of all, laughing as he sat on top of a pile of dead bodies, including his own… eternal, immortal, unstoppable.

He wrenched the second-to-last goblet from Kreacher's hands, and drank it himself. "I'm going to destroy you, Dark Lord!" he shouted as Kreacher cried. "You're going to die, Voldemort- you're going to be mortal, Tom Riddle!"

His insides burned, worse than any cruciatus curse. Kreacher tilted up his head and shakily poured the last of the potion- a word so cruelly similar to poison- down his throat. He saw Kreacher switch the lockets, and then lean against the basin, sobbing, the Dark Lord's locket in one hand, the goblet falling from the other.

Water. The word was almost placed into Regulus' mind. Regulus crawled to the lake.

"Master Regulus!" Kreacher cried. "Come back, Master Regulus?"

He's lying, a nasty voice said in his head. He wants the water all to himself.

Regulus dipped his hand into the water, and gave a cry of surprise as a pale hand grabbed his own. It pulled.

And then a hundred others did. Regulus was pulled into the water.

"Kreacher!" he screamed. "Kreacher- please!"

Kreacher wailed as Regulus was submerged into icy water. The Inferi were stronger than he could have ever thought- a thousand rotting hands, pulling him, drowning him.

Never had his thoughts been clearer. His hand stretched up towards the light, hoping someone would pull him back up before he was too far down. But it wasn't Kreacher his hand searched for. He closed his eyes, imagining Sirius' hand dragging him back off. He imagined Sirius, pulling him close, fighting off the Inferi. Sirius, his disowned, disgraced brother. Sirius, who hadn't spoken to him since his sixteenth birthday. Sirius, who would take him to Hogsmeade and get him a butterbeer to warm up.

An inferius closed an arm around his chest, dragging him further down. He imagined it was Sirius. Any minute now, the muggleborn, Lily Evans, would summon them up from the lake. Any minute now, any minute now, any minute now…

His hair and robes and tie swirled above him. He opened his eyes, and he could only see darkness.

And he died.