The world of his birth is long gone, destroyed in the Time War, but even before that he was a drifter, travelling from planet to planet and through all of time. He’s been doing it for so long now it’s become a way of life; he can’t imagine any other way of being.
He never stays anywhere for long, has no need to settle and put down roots. He takes his home everywhere he goes, or perhaps more accurately, she takes him. The urge to travel is something they share; the universe is so immense, holds so much wonder and mystery, neither of them can bear the thought of just staying in one place. There’s too much to see, and even a Time Lord only gets so much time.
With each new regeneration his wanderlust seems to grow stronger, a ceaseless urge to see whatever lies beyond the next horizon. What he finds there isn’t always beautiful; there’s as much pain and suffering as there is peace and tranquillity. But maybe that’s the point of travelling, to seek out the places where suffering exists and make things better. It gives him a purpose, to help those in need, regardless of species. He gets to meet a lot of interesting people that way.
One day, he knows he’ll reach his final regeneration, and then he’ll just keep getting older and older until he’s no longer able to live the life he’s chosen for himself. In a way, he hopes he doesn’t live long enough to see that day. For now though, he’ll just keep going, exploring and experiencing everything he can, making friends and enemies along the way and always looking towards the next horizon. He knows he’ll never be able to see everything, but it won’t be for lack of trying. The universe and all of time is his playground, and he plans to make the most of it, for as long as possible.