"I don't care I got to keep the TARDIS, you got to keep ROSE!".
Silence.
Clara Oswald stood back in awe as The Doctor blushed wildly, and the 'other Doctor' stared.
It's a wonder how the accidental flick of a switch in a type 40 TARDIS can transport you to parallel worlds. Literally.
The Doctor knew it was a bad idea; he shouldn't ever have come back. Even though it was an accident, he could've stopped it. But he wasn't going to tell Clara that.
Of course, they arrived 5 years after Rose was stranded like an unwanted toy (or Adam in Supernatural*wink*) and Rose clearly had moved on. Hell, she wasn't even angry he left her the way he did. She'd moved on, with a ring on her finger and a small, vulnerable life form in her arms.
It was time The Doctor did too, after all, he was technically a married man.
