I'm disclaiming, because I don't own Harry Potter (or all that money) he belongs to J.K Rowling. Nor do I own Doctor Who, oh and disregarding Amy and Rory's exit from the series, they decided to adopt and have almost permanently left the Tardis, so the Doctor's used a computer program he made to pick the perfect companions.
The Travelling Man
Chapter One - That man in a blue box...
Harry, Ron and Hermione were lying on the grounds outside the partially destoryed castle. They were staying at Hogwarts for a bit, to help with the cleanup. Ron and Hermione had already admitted they loved each other to Harry, who had said, "About time." Ginny had started going out with Harry, but Mrs. Weasley had taken her home to organise Fred's Funeral. They would cremate him and spread his ashes outside the Burrow, the shop and Hogwarts. A man came running round the corner.
"Who'd you reckon that is?"
"Not a photographer, they're up in London, covering the captured death eaters, they're waiting for me to go down there for my story for once." Harry answered. Ron lifted his head, the man had on a bow tie, tweed jacket and skinny trousers.
"Got to find them, they're here somewhere..." He jumped over Ron.
"Are you looking for us?" The man landed, spun round and eyed Ron.
"I might be, who are you?"
"Ronald Weasley."
"No, you can't be. Well it is plausible, but not probable, and how could I be here, that Universe would be sealed." The man continued to ramble.
"Sir, I'm sorry, but what do you mean? You said 'that Universe' you mean there's others?"
"Of course there's others, you're Hermione." the man said, as a statement, not a question.
"How do you know? You didn't know Ron."
"I wasn't paying attention to 'Ron' was I!" The man said Ron's name with a shake of his head, to indicate that Ron wasn't very important.
"No, it's more than that, you're saying that we shouldn't exist, or that our we don't exist in your Universe, which seems to indicate you are from another Universe, which is impossible..." The man interrupted her, "No, just implausible." Hermione continued, "Yes, but as we have not achieved travel between Universes,"
"Just because you haven't doesn't mean to say I haven't." Hermione huffed,
"You also said that 'that universe would be sealed,' and that you didn't know how you could be here."
"Are you always like this?" Hermione looked like she had been petrified, her eyebrows shot up and her face froze.
"I have my theories about why I would be here. I created a program on my ship computer to find me the perfect companion or companions,"
"Companions?" Ron asked,
"Sometimes I travel with more than one, it stops me from going too mad," Harry and Ron exchanged looks, "So I created a program on my ship's computer,"
"What's that?" Ron asked,
"A machine used to help me work my ship." Ron gave a look that said 'muggles' "A program to find me the perfect companion,"
"Why'd you do that?" Harry asked.
"I was having a long and boring day."
"Don't we all."
"No, I was repairing my ship on a planet where the days were 67 hours long and the populace were all middle-aged vicar's wives, not much fun I can tell you. It came up with you three and took me to you, I think it punched a tunnel through the void from my Universe to this one. Very odd, I'll have to take a look later."
"And we're you're perfect companions."
"Yes, the hero, the genius, the mad man with a box, and the ginger."
"Oh thanks, thanks alot." Ron muttered.
"Who's the mad man with a box?"
"I am." The man said.
"Well we can't call you that. What's you're name."
"The Doctor."
"Just 'The Doctor,' nothing else."
"No, nothing else."
"Why d'you think we were picked."
"It may have something to do with Harry here."
"What do you mean it may have something to do with me?"
"Well, you're the Master of Death. I'm the Lord of Time. Don't you think that would be the best double act ever." The trio stared at him like he was mad.
"Ohhhh, never mind." Harry opened his mouth,
"What makes you think we'll come with you. We have lives, responsibilities, we have a whole world that we belong to, we're famous, we can't just up and leave!"
"Why not."
"Because..." Harry protested.
"I'll put it differently. All of time and space, everything that ever happened or ever will, every planet, every moon and star, days long dead and hours undreamed of for milleniums, each person, each place, each moment, every piece of magic and mystery, every adventure and every dream. Now are you sure you'll stay?"
"You can time travel?"
"Follow me." They walked with the doctor to a blue telephone box.
"It's a box."
"I know, that's why I'm a mad man with a box." He clicked his fingers, the doors opened.
"It's, it's, it's, Doctor, is this an undetectable extension charm?" Hermione asked,
"No, but good guess, it's in another dimension, most people just say it's..."
"It's bigger on the inside!" Ron exclaimed. The Doctor turned around and said, in the voice of McGonagall,
"Thankyou for that assessment Mr. Weasley." Ron jumped.
"Don't do that."
"My apologies. So are you coming..."