Sirius paced the halls of the home he hated so much, throwing murderous glances at the pictures as he passed, who were muttering under their breath words like 'blood traitor', 'filth' and 'muggle lover'. It was something he had grown used to during his childhood, especially once he had started Hogwarts and distanced himself so far away from the family values that he was barely welcome at home. He could not deny that life was better now; he was out of Azkaban and he had regained his old friends, specifically, Remus. He could not describe his joy at his blossoming relationship with Harry, who was like the son he never had and having his best friend back combined into one brilliant boy. He was, however, still locked up, trapped in the house he could not stand. It was almost like being back in his miserable childhood, stuck with a family he despised. He was, at that moment, waiting for Dumbledore to explain why he was, like a troublesome schoolboy, not allowed to leave the house. Whatever the reason, he thought, glaring at the Black family crest, whatever the reason, it had better be really good.
The fire burned green and Dumbledore emerged. Sirius proffered his hand and said, not bothering to keep the sarcasm out of his voice, "Welcome, good sir, to my humble abode," Dumbledore looked at Sirius over his half moon glasses for a moment before muttering, seemingly to himself,
"Ah yes, that," he opened his mouth to speak again but Sirius cut him off, launching into his own argument.
"Look, I know I'm a wanted criminal and it's unsafe for me to go out but there are ways, all sorts of ways. Polyjuice Potion, charms that can change my appearance, even if I can't use my dog form any more -" Dumbledore raised his hand for silence and Sirius stopped talking immediately, even though he was itching to continue,
"Do you really think I haven't considered these options?" he asked lightly, his eyes twinkling,
"Then why -"
"Haven't you considered that all the member's lives are in danger when they go on Order business? That there might be some reason why I wanted to keep you safe?" A hint of steel had entered Dumbledore's voice. Sirius gave a half shrug. He had not expected this. Dumbledore looked mildly disappointed, like a teacher whose favourite pupil had failed him, "I am keeping you safe, Sirius, simply because Harry needs you to remain safe, alive and out of Azkaban. Harry also needs you to be a readily available correspondent and confident, to help him through what he will have to go through. Harry is going to have a tough year, the toughest he's had yet and I cannot help him. In fact, I will have to distance myself from him, which will make it tougher, he will feel abandoned and alone. That is unfortunate, but sadly necessary. You know why. He will need someone to talk to, someone who understands what it is like to be vilified and hated, someone other that Ron and Hermione. Quite apart from that, you are the only family Harry has and he would be devastated if he lost you," Dumbledore paused and seemed almost imperceptibly older, "he has lost too much, Sirius, and I don't think I could stand it, I especially don't think he could stand it, if he lost any more," Sirius nodded. He would do it, he decided. He would submit to being trapped in the place he had thought he had escaped, for Harry's sake. Dumbledore laid a hand on his shoulder "I'm sorry Sirius, I know you wanted to fight but -"
"No, it's all right, really, it's all right. It's like you said, it's for Harry," Sirius gave a wry smile, "I think I would do anything for that boy,"
"That is good to hear," replied Dumbledore, the twinkle back in his eye, "because I think Harry would do anything for you," and with that Dumbledore, chuckling to himself, disappeared back into the fire, leaving Sirius to his thoughts. Sirius smiled his first true smile in a long time. Harry would do anything for him. Life was good again.
A few weeks later Sirius' impatient waiting was over, nearly. As per Dumbledore's instructions Sirius had not been allowed to actually go and collect Harry, but Harry would be arriving here soon. The house, for the first time, seemed a little brighter, an almost bearable place to be. The painting's mutterings didn't bother him and even his mother's screaming only made him laugh. Sirius didn't think that even Voldemort could spoil his mood. He would be seeing Harry again so very soon. He heard the door open slowly as they entered whilst trying not to disturb anything or anybody. Tonks inevitably knocked something over. Sirius grinned, Harry had arrived.
I'll stay alive for you Harry. I'll stay alive, safe and out of Azkaban for you, and I'll always be there for you Harry, I'll listen to you whenever you need me to and help in any way I can. I'd give my life for you Harry, but as it is I'll just live for you. You won't lose me as well. I promise.