Disclaimer: I don't own anything!

Summary: After the Tri-Wizard tournament, Harry runs off to Wizarding London. There he stumbles across an alternate version of himself, a boy called Corvus. Corvus then takes it upon himself to fix the problems in Harry's world, by whatever means necessary.

Other notes: Corvus's back story is currently being written in my story Harry Potter and the Marauder's Den. This story is mostly Remus and Sirius centric and takes place Pre-Hogwarts. The story of Corvus's Hogwarts years and how and why he began dimension traveling hasn't been posted yet, but it will be soon under the name A Beginner's Guide to Dimension Hopping.

Harry Potter and the Dimension Hopper

There was a boy sitting at the table when Harry got there, his table, the one he'd been sitting at all summer. Not that there was anything wrong with that, exactly. It was just that the boy had a lightning bolt scar on his forehead just like his own.

He obviously knew Harry was gaping at him, but he simply smiled a little absently and continued to stir his drink. "Have a seat," he said.

Harry did.

Upon closer inspection, he noticed that the boy did not resemble him at all. He had deep grey eyes like Sirius's, and dark circles under them to match. His cheek bones were high and aristocratic and his chin was pointed like Malfoys. His beak nose looked like it had been broken a few times. His hair was dark and shaved on the sides, and he had a lean, wiry build.

He seemed to be waiting for Harry to say something.

"That's my scar," was the first thing that came out of his mouth.

The boy smiled faintly. "So it is," he agreed.

"I'm Harry," he blurted.

The boy's mouth twitched in silent laughter. "I know," he said. He held out his hand to grasp Harry's. "I'm Corvus."

Harry looked around suspiciously. "Were you waiting for me?"

"Naturally," he said, examining his nails. They were long and pointed and painted a deep maroon. It took Harry a moment to realize that Corvus wasn't wearing robes, but a beat up leather jacket and torn, faded jeans. "I always seek out my alternate self when I hop to another dimension. Don't you?"

Harry stared at him. "Dimension? Alternate self?" he squeaked.

Corvus paused. "Ye-es," he said slowly. "Don't they teach that in school? The theory of time travel? Alternate dimensions? Magical science?"

"Er, no."

The other boy blinked at him. "Ah, well," he said. "Times change."

There was a pause and then, "I wouldn't mind if you – you know, explained a bit?" Harry offered, only slightly disbelieving.

Corvus' mouth twitched again. "Of course you wouldn't," he said. "Every choice you make creates another dimension. For example, you appear to be spending your summer in Knockturn Alley. Currently, there is another dimension layered on top of this one in which you went home this summer, instead. It's like, an endless stack of parchment that keeps on building up. And you can hop between them, if you know what to look for."

Harry gave him a disbelieving look. "You're not serious."

"No, I'm Corvus," he deadpanned.

Harry looked blank.

Corvus shrugged. "I thought it was funny," he said.

"What's the difference between your dimension and mine?" Harry asked.

Corvus shrugged. "Someone made a different choice, and it set off a chain of events. It could have been anyone, anyone in the whole world." Corvus reached into a pouch around his neck and pulled out a heavy book. "I'm actually doing a bit of research for the Department of Mysteries back home. Categorizing the different dimensions."

"What if you never get home?"

Corvus shrugged. "Tell me about yourself," he said, getting out a quill. "Your House, your friends. Family. Details."

Harry squared his shoulders. "I'm in Gryffindor. My best friends are Ron Weasely and Hermione Granger."

"Ravenclaw," Corvus told him, scratching that down. "Theo Nott and Draco Malfoy."

Harry choked. "Malfoy?"

Corvus quirked an eyebrow in response. "Weasely is a chauvinistic pig," he said. Well perhaps not his Weasely, but several Weaselys whom he had met in the past few dimensions. "And I believe Granger was killed in first year by a troll." Or had that been some other Granger? " Family?"

"Only the Dursley's," Harry said, reluctant to claim them as family. "And I have a god father, Sirius Black."

Corvus hummed noncommittedly. "Interesting. What about Remus Lupin?"

"Professor Lupin?" Harry asked, bewildered. "What about him?"

Corvus frowned. "I see. Why are you with these…Dursley's, if Sirius is around?"

"He's a convicted murderer," Harry admitted. "And a fugitive."

The other boy's frown deepened. He snapped the book shut and stood up. "Potter isn't it? You can trust I'll be in touch."

Harry found himself gaping again. "You can't just dump all of that on me and walk out."

Corvus waved a hand dismissively. "Do you mind if I borrow your name a bit? I have some research to attend to and I can't use my own without there being an issue."

"You look nothing like me," Harry protested. "And what is your name anyways?"

Corvus hesitated. "Black," he said finally. "Perhaps you could do yourself a favor and find some books about dimension hopping while you're waiting for my owl. I'll see you around, Potter."

With that, he stalked off in a fashion very reminiscent of Snape.