"You…what did you do to him?" the Doctor spluttered, gesturing vaguely at Jack.
"Correction – what did Rose do? She thought she was doing the right thing. Of course, you had to go and kiss her, take it away before she did the job." Rose stared blankly at him.
"I had to! She was dying!"
"She still is. I told you, she didn't finish the job. Why do you think it hurt so much? Rose hated the fact that you were always so alone. She tried to change that. Stupid human."
Hearing those words, the Doctor exploded.
"Rose is not a stupid human! Not my Rose!"
"Stupid, yes. Human, though, is now another matter." She took a step nearer the Doctor, a smile growing on her face as though she derived some sick pleasure from her words. "She loved you. She loved you enough to take all that power, to save you, and make her, and him, like you. It hurt her. It burned. It was flame, and ice, and wind and rain and knives through her new hearts all at the same time." Rose laughed, edging closer. "Only you had to jump in, didn't you? And they are not complete. That is why he still appears as he did when you first met him. If you had let her, she would have died to return them all to you."
Jack jumped forward, suddenly, and hating himself for it, took Rose by the throat. "What are you?" he snarled.
"I am the wolf."
"You're not. Rose is, and she wouldn't do this." Jack's grip tightened.
"I am her fear. I am the hatred she turns on herself every time she remembers that she killed her Doctor. I'm her pain and her sorrow," she looked at the Doctor, laughing. "She hates herself. She corrupted the wolf into me, and I have her now, and I will soon have destroyed all that was left of your Rose. And do you know something? She's terrified."
The Doctor didn't react as Jack expected. He held a hand up for the captain to let her go, then said, "Rose, I know you're still there somewhere, and I know you don't give up that easily. Fight it. Talk to me, Rose."
Then something happened. The smile faded, and although it wasn't the reaction the Doctor wanted, it was better than it could have been.
"I can give her back to you. But you have to give me something. I want a body."
"I'm not going to sacrifice someone else to you."
There was an awkward silence, and then Jack spoke up. "What about me?" he stammered.
"Jack, no…" the Doctor began.
"You are suitable. But will you die for her?"
Jack looked at the Doctor then back at Rose. "No question. I told her once that she was worth fighting for, and I meant it. I want something in return, though."
"Which is?"
"I want you to put everything back the way it was. I want Rose to live."
"I will do as you say. You have made your choice," she said, "but now the Doctor must make his."
"What is my choice?" the Doctor asked, nervous.
"I can give Rose back to you as she was before she saved you, and you will watch her age and die. Or I can give you this body, and you will be the one to comfort her through the loss of all those she cares for as she lives on."