Prologue
Rose had known, no matter what Jon told her, that things would change when he took the Doctor's conciousness into himself. Yes, Jon was the Doctor. But he was also Donna. Something had to give, there was only so much room, Time Lord brain or not.
She noticed it right away. Anytime there was a "first" since the assimilation. The first time he picked up Arianna. The first time he hugged her. The first time they made love. The first time he went into the office. The first time they ate out. Hell, the first time they did anything. He was constantly either on the verge of tears of joy, or in ecstasy.
It was Jon all over again, in a way. He was re-discovering what it was to be human.
Oh, Jon was still there, to be sure. The way he ran his fingernail up her backbone when she least expected it, in very innappropriate settings. Only Jon knew how that drove her crazy with lust. The way he knew which of his students he could pick on unmercifully. The way he knew just how to tickle Tony to reduce him to hysterics. He had the public transportation schedules and routes - regular, holiday, and emergency - committed to memory. Everywhere. He knew exactly what was on the telly at any given time, on any given station, anywhere in the world. Yes, Jon was very much still there. But he was different.
The most pronounced difference was the attitude toward he approached "work". Jon previously was all about developing Earth's defenses. Now he was more concentrated on developing alliances, and growing the baby TARDIS - secretly. He hadn't actually started yet, he needed to find the right place first. Rose was in on his plan. What else could she be?
She prayed he would find a way to get the three of them off this planet, and to a setting where Arianna would fit in, and she wouldn't have to hide her superior intellect.