The siblings' room was rather simple, without much in the way of decoration. There was a small Christmas tree by the dining table with two wrapped gifts beneath it, likely prepared in advance.
Following Miguel upstairs, Cohen passed an empty bedroom with the door ajar. Through the gap, he could glimpse a few drawings stuck to the wall. They were unmistakably pictures of Cohen himself, along with a portrait of a Dementor he didn't recognise.
"!" Miguel quickly slammed the door shut. "That's—that's..."
"I'm used to it," Cohen said.
At least this person hadn't kissed his robes. A silver key that wasn't a Death Eater's was a little more normal, though still not entirely so.
In the second bedroom, Cohen saw Carlton. Just like her brother, she had a head of grey hair, but her complexion was much better than Miguel's. Due to years of not seeing the sun, she was incredibly pale—but it was better than a waxy yellow.
"You're..." Carlton stared blankly at Cohen.
For a moment, Cohen couldn't tell whose complicated emotions were fluttering around the room.
"Cohen Norton, the Butter-Unicorn," Cohen said, raising an eyebrow.
"What's a Butter-Unicorn?" Miguel quickly turned his head to ask Cohen.
"It's a nickname. I think it's quite cute," Cohen replied.
"Pffft!" Carlton covered her mouth, stifling a laugh.
In the short time he'd been in the room, Cohen had already detected the curse on Carlton. The good news was it wasn't a soul-based curse, so Cohen could fix it.
"I have some good news for you. I can solve your sister's curse," Cohen said.
"Really?" Miguel's eyes widened. "You mean—she can stand up—I... I..."
"Don't say the next thing you're about to say. As I told you, the other half of our deal is for you to give me everything you know about the Silver Key," Cohen said. "And I'm not finished talking. Do you mind if your sister gets a new body?"
"A new... what?" The redness in Miguel's face drained away.
"A new body. Even if the curse is gone, her legs won't work," Cohen said, pointing at Carlton's legs on the wheelchair. "I can create a new body for her and then transfer her soul into it. Aside from making the body, transferring a soul is as easy for me as eating a meal."
"Will she be hurt?" Miguel asked.
"I am a Dementor with excellent self-control," Cohen said. "Don't doubt my professional abilities. If you don't trust me, I can find another professional Dementor to do it."
"No—there's no need to find another one—" Miguel quickly waved his hands. "Then... what about you, Carl?"
He looked at his sister.
"I want to walk like a normal person," Carlton said, swallowing as she looked at Cohen. "I want to go to Hogwarts... I want to..."
"How old are you?" Cohen asked.
"Fourteen," Miguel nervously answered for his sister.
"Write to Dumbledore and explain the situation. I think he'll let you enrol," Cohen said. "But you'll have to learn some proper magic first. You need to forget everything you've learned before. Dumbledore doesn't like the Dark Arts."
"Really?"
"Wait—the Dark Arts?" Miguel looked at his sister, confused. "Who taught you that? What Dark Arts?"
"Werner and Earle taught me," Carlton said. "They said it's what all Hogwarts students should learn..."
"Things like the Cruciatus Curse, the Imperius Curse, the Rotting Curse, and so on," Cohen said. "Your sister is quite talented. It took me ages to learn those."
"What?! They made you learn that?!" Miguel said, furious. "I thought they only taught things like the Levitation Charm—"
He even forgot to wonder how Cohen knew all of this when he himself didn't.
"I don't like those curses, so I always pretended I hadn't learned them..." Carlton said, looking down.
"It won't make a huge difference if you don't use them. I know a ton of Dark Arts myself, but I turned out to be a very righteous and kind person, didn't I?" Cohen said.
Cohen's words didn't make Miguel feel any better. Miguel had heard about what Cohen had done: the 'one-year, 300-kill' spree, hobnobbing with You-Know-Who, assassinating the Minister for Magic...
"You seem to have a sliver of doubt about my kindness?" Cohen narrowed his eyes.
"No!" Miguel said immediately.
"Alright then. Since you both agree, I'll begin," Cohen said. "Do you want to stay here? What's about to happen might be a bit stomach-churning, especially for a brother to witness."
Miguel shook his head, unwilling to leave. He wanted to see his sister get better—and he couldn't quite believe that a person's soul could "change bodies."
"That's fine. You'll have to help put clothes on her new body later to save some trouble," Cohen said. "Otherwise, I'd have to wrap her in a bedsheet before the body is even fully formed..."
Though he didn't understand what Cohen was talking about, Miguel didn't dare ask too many questions. As long as his sister got better, a scary process was worth it...
Then, Cohen pulled out the jar containing the mass of flesh he'd cultivated the night before. Carlton and Miguel both gasped when they saw the fleshy, pulsating, and vein-covered lump.
"There's no need to look at me like I'm an ancient deity or something..." Cohen unscrewed the lid of the jar and pursed his lips. "Although, with a few tentacles and eyes added, it would definitely have that ancient-deity-from-a-novel feel... But this is proper alchemy."
"Add some blood in," Cohen extended the jar towards Carlton.
Fearing his sister would be too reckless, Miguel grabbed his wand and stepped forward, carefully making a small cut on her hand, and then a single drop of blood fell into the jar.
"You're afraid your sister will faint from a few drops of blood, aren't you?" Cohen said, rubbing his forehead. "Her body is about to be replaced. Give me more."
"Won't this be too dangerous..." Miguel said, his heart aching.
"If we don't save her, she only has a few months left to live," Cohen said.
Though, even if she was saved, she might still only have a few months to live, just in case the person hanging in the Department of Mysteries in the prophecy was Carlton herself.
After a moment's thought, Miguel finally hardened his heart and allowed Carlton to give a little more blood. Even then, the actual amount was less than what a person gives in a normal blood donation.
"Episkey." Once Cohen said it was enough, Miguel immediately healed his sister's wound.
The mass of flesh began to swell. Cohen poured it onto Carlton's bed and turned his back.
"You should pay attention to putting clothes on her new body. I don't want to take any liberties—wait... I have an idea..."
Cohen suddenly muttered something under his breath and, while keeping his back turned, cast a Colour Change Charm in her direction with his wand.