The Doctor Rose knew, and over protective of Rose. Rule number one, she was certain that the Doctor was from further along his own time line than he admitted. But he matched himself to Rose, for her sake. She nodded once. That made sense. But it still didn't tell her if he would know who she was already, had he been to the Library? If so... he was ahead of her. And behind.

But she didn't know. Until she met him, she wouldn't know.

"I am not a Time Lord," she confirmed. "If the Doctor doesn't know what I am yet, I can't tell you," she said, apologetically. "But.. she smiled a bit. "You will most certainly be sharing him. Don't worry, two hearts, if we each get one that's still more than anyone else ever gets from him, yeah?" She was acting more flip, calmer. She didn't see it that way at all. But she had a feeling that was the right note to take to keep Rose from asking more than she could answer.

And the Doctor wasn't the only one... who lied about important things.