Here there be Book 5 spoilers. Ye be warned.

He learned to smoke from Sirius. It was one of those unusually clear nights that clustered around the start of the year, when Harry was staying at Grimmauld Place for Christmas. His head full of worries and serpentine dreams not of his own mind's design, Harry wandered up to the attic and discovered his godfather perched in one of the narrow windows, pulling a cigarette from his lips.

Wizards smoked pipes, but Harry thought cigarettes were a Muggle invention.

"They are," said Sirius. He exhaled and the smoke looked briefly as if it took the shape of a dog. Harry wondered if Sirius was doing it on purpose. "I picked it up from your mum, actually. I'd do anything to push Mother's buttons."

"Did it work?" Harry guessed it did, knowing the portrait Mrs. Black's reaction to anything Muggle.

Sirius snorted. "Irritated her worse than a bat up her nightdress. That I would pick up a filthy Muggle habit like smoking pissed her right off." He jammed the butt of the cigarette against the windowsill, then tossed it into a tarnished silver soup tureen. Sirius must have fought Kreacher for it; the house-elf was rabid about caching the family heirlooms away from Muggle-loving paws.

Harry smiled at this, but it was a hollow smile.

"What's wrong?" Sirius asked, pulling two more fags from the pack. Harry raised an eyebrow at this, and after only a second's hesitation he plucked the proffered cigarette from Sirius's hand.

"I just feel helpless," he said. "Everyone knows so much more about what's going on than I do. I hate being helpless. It's exhausting."

"I think I know what you mean," said Sirius. Harry colored. Sirius was even more bound by the outside world than he was. At least Harry had his freedom.

"Sorry," he said. Sirius threw a too-thin arm around his shoulders.

"Lean in here," he said, producing his wand to light their cigarettes. "Careful. Take it easy or you'll cough and wake Molly. She'd have a fit if she knew I'm corrupting you."

Harry smiled at the thought of Mrs. Weasley catching them, as if they were sneaking an illicit smoke in the school bathroom.

"Sirius?" he asked after the burning in this throat from the first drag subsided, "Why are you still smoking if your mum's—"

"Does she sound dead?"

Harry thought of the painting's murderous screeches and grimaced. "No."

"Exactly. If I can't get her off that wall, she'll have to deal with me sneaking a cig every once and again."

There was another amiable pause between them, and Harry's mind had finally wandered to more pleasant topics when Sirius spoke again.

"And if I'm going to go," he said firmly, "it's going to be on my terms. They're my damned cigarettes. They can't take that from me." He took another drag with relish.

Harry thought of basilisks, graveyards and the nightmare snake, and of the walls behind Dumbledore's eyes.

He lifted his cigarette to his lips and inhaled.