Author's Note: Written for the "Writer in a TARDIS" fic challenge on LiveJournal. I don't own it.

I

"Really though, Doctor. Tell me - who are you?"

She was persistent. Time was when he liked human persistence, rewarding them for it with a glimpse of the universe. A look at the fiery birth of a new star, springtime in the Eye of Orion, the founding of a new civilization.

He still liked human persistence. But he wouldn't take any more with him, no matter how much he liked them. It wasn't right to take people he liked into danger and death. And he liked her.

So he gave her a cryptic answer that wasn't an answer, and told her the one thing he wanted her to understand. "Now, forget me, Rose Tyler."

II

"It couldn't kill Van Statten. It couldn't kill me. It's changing. What about you, Doctor? What the hell are you changing into?"

He stared at Rose and the Dalek, both standing in a shaft of autumn sunlight. Every fiber of his being shouted that he had to destroy the Dalek before it rose up along that shaft to escape and kill millions. The flames of Gallifrey rose up before his eyes, the voices of his dying people screaming in his memory.

This was a Dalek. This was the enemy.

But Rose didn't see an enemy at all, even though she'd already seen it kill. She saw a sick, wounded alien, and she was standing by it, waiting for his answer.

He didn't know what to say, what he was becoming.

So he told her the one thing he did know. "Oh, Rose. They're all dead."

III

"What did you say?"

He focused more intently on the device he was putting together. He hadn't mentioned being a dad to anyone in years. That was another life, in more ways than one, as different from his life now as winter was from summer.

Somehow he'd let his guard down with Rose. That was becoming a habit. He wasn't sure if it was old age, or this personality, or just the way Rose had managed to blast past nearly all of his barriers, save one.

No, he wasn't going to have this conversation with her. It would lead to conversations about doors and carpets and if he'd done it before, why couldn't he do it again?

He had already crossed so many lines with Rose. But he wouldn't cross this one.

So he changed the subject to the Isolus, and told her the one thing he dared. "You know the thing you need most of all? You need a hand to hold."

IV

"And how was that sentence going to end?"

She was watching him intently, the winter wind blowing her hair about her face. She still was persistent. But then, she always had been, and that was one of the things he'd liked about her from the beginning.

Loved about her from the beginning.

Not that he ever told her that. Not that he ever could tell her that.

So he told her the one thing he could, even though he knew it would break three hearts.

"Does it need saying?"