Her Thief didn't want her to see what he was doing, not that he could truly hope to conceal it from her. He walked miles, and miles, and miles, on legs that could barely carry the weight of his own body anymore, let alone the terrible burden he bore on his back.
He felt so alone, so very alone and without hope. The universe was burning all around them, chaos and death and despair raging in every moment. And he knew of only one way to end it, to save the universe at the cost of his soul.
No, her Thief didn't want her to see what he was doing, didn't want her to share the shame and grief and horror for what he was about to do. Her beautiful idiot, he still didn't understand, even after all these years, she was with him wherever she went. He was never alone. For the love of him, she shared his pain whether he wanted her to or not.
A fragment of her eleven-dimensional consciousness in the Now shadowed his mind, wishing she could offer him some sort of comfort. But it was not the Time When They Talked. She could not speak with him in the simple linguistic communication of beings of flesh, she could not make him understand.
She reached out and touched the Moment, concealed in a burlap sack on his back. The Moment was a weapon, a truly terrible weapon, a galaxy-eater, but she felt a sense of shadowy kinship to it. Bottled time, it had developed a sentience of its own, and it answered her call. It understood its purpose, its reason for being, was death and destruction on such a massive scale that even the ancient Time Lords who crafted it during the Dark Times had locked it away in the forbidden Omega vaults.
Yet it was innocent, an unformed thought that was still beginning to wonder Is there nothing more?
The Moment answered her touch with a questioning probe of its own. Like a mother embracing a child, she opened her heart to it, welcoming it into her being. It responded with a sense of wonder as it realized that she was spread across all of time and space, yet simultaneously contained in the form of a wooden box, painted blue, miles and miles away.
She could feel their connection changing the Moment as its consciousness danced up and down the time stream she shared with her Thief. It was Becoming, taking shape in a manner so intimately influenced by her connection with her wonderful Thief.
It saw the death of Gallifrey, and how it would break his hearts. It heard those final, despairing words, No More. Then she showed it something, a precious union she had shared with one of the dear strays he had brought back, a being that would know exactly what needed to be done.
I am the Bad Wolf.
All of Time, embodied in the frail form of a girl from the Powell Estates in London.
The Moment smiled, thanking her with sweet lips, and kind brown eyes, and blonde hair that floated about like a cloud.
The choice still remained before him, and of the multitudes of possibilities there was but one delicate, fragile, but infinitely beautiful path between disaster on one side and destruction on the other.
Oh, yes, her Thief may not have wanted her to see what he was doing, but she was with him anyway. For no matter what he called himself, he was still the Doctor, and she was still his TARDIS.