Disclaimer: I don't own Harry Potter.
In the middle of the dark road on Grimmauld Place stood a man who was staring between houses number eleven and thirteen. Slowly, the two houses moved aside, revealing another between them.
For the first time in almost twenty years Sirius Black walked up the stairs of Number Twelve.
"Home, sweet home," he thought bitterly as he entered the place he hated most, slamming the door loudly behind him.
"BLOOD TRAITOR! FILTH! SCUM! SHAME OF MY FLESH! HOW DARE YOU RETURN TO THE HOUSE OF MY FATHERS! - "the portrait of Walburga Black started screeching.
Sirius hurried towards the painting and struggled to cover it.
"Always nice talking to you, Mother," he grumbled, as he finally pulled the curtain shut over the screaming portrait.
The house became completely silent. He looked down the dark hallway. Every surface was covered in a thick layer of dust. He could see the dark shapes of the heads of the house-elves on the walls. To say that he was unhappy about being back would be a big understatement. However, he was still considered a wanted criminal by the Wizarding World, and had to remain in hiding.
Dumbledore had re-formed the Order of the Phoenix and Grimmauld Place was to be used as headquarters. It was protected by a Fidelius Charm cast by Dumbledore himself and various other protective spells that had been cast by his father years ago.
Sirius sighed. Offering the house to the Order was the only helpful thing he was able to do. He was absolutely useless.
The reason the Order was being reformed was because the Ministry of Magic refused to acknowledge Voldemort's return. Cornelius Fudge was determined to make Harry look like a self-centered, attention seeking lunatic. Of course he didn't realize that by ignoring Voldemort's return, he was helping him, giving him time to become more powerful.
Idiots, Sirius thought, spitting on the filthy floor.
He took his wand out of the pocket of his tattered robe.
"Lumos," he muttered. He held the lit wand in front of him and began to walk further into the house.
Sirius caught his reflection in a mirror hanging on the wall. Azkaban had taken its toll on his looks. He was no longer the effortlessly handsome young man he once was. His skin was pale, his face gaunt, and his cheeks hollow. His hair was long and tangled and he really needed a shave. His grey eyes were tired and framed by dark circles.
Sirius shook his head and continued down the hall until he reached the staircase. Buckbeak was in his mother's room upstairs, waiting to be fed.
On the topmost landing he saw a door with his name hanging on it. Sirius opened the door and entered his old bedroom.
The entire room was decorated in red and gold and a large Gryffindor banner hung on the wall. The rest of the walls held various pictures of bikini-clad Muggle women on motorcycles. His mother had been furious with him, but was unable to remove them thanks to a permanent stick charm. Sirius smiled to himself. He had wanted to set himself as far apart from his family as possible.
Sirius walked up to his writing desk and opened the top drawer, taking out an old photograph. Two sixteen year old boys were standing outside Florean Fortescue's Ice Cream Parlour, holding two large ice-cream cones. Both were grinning broadly.
One had untidy black hair and round glasses. The other had shoulder-length black hair.
Sirius grinned, remembering the day the photo was taken. During Christmas holidays in his sixth year he had had a big fight with his mother and had stormed out of the house. Using their two-way mirror he contacted James and they spent the entire day at Diagon Alley.
Tears began to well up in Sirius's eyes. He missed James so much. He had never felt worse than on the night of October 31st in Godric's Hollow: seeing James lying lifeless on the floor, his eyes wide-open but seeing nothing. He cursed Voldemort for murdering his best friend. He cursed Wormtail for betraying James and Lily.
Sirius couldn't believe that people thought he would ever serve Voldemort; that he was responsible for the deaths of his best friends. And yet in a way he was. James had wanted Sirius to be their secret keeper, but he had declined, thinking it would be less obvious if it was Peter. How could he have been so stupid as to trust Peter with something so important? Wormtail had always been the weakest and the most cowardly of the Marauders. Clearly they had underestimated him. He was smarter and more cunning than they had ever given him credit for. Why hadn't he just killed the bloody rat when he had the chance? Why hadn't he just gone along with James's plan? If it hadn't been for him, James and Lily would still be alive.
Sirius looked down at the photo of the laughing boys once more.
"I'm sorry Prongs," he whispered as tears fell from his eyes.