Disclaimer: Sadly, I don't have any claim over "Harry Potter" or anything else you recognize (unless it's from one of my other stories)

Author's Note: I'm not sure yet whether this is going to be a two-shot or a full (albeit not very long) story, as I'd originally planned. I'm leaving to work in Cambodia in ten days, so I'm going to try to finish all my in-progress fanfics before that! Please review and let me know what you think!

Summary: Hermione had made him a promise, and she never went back on her word. But keeping it turned out to be harder than she'd imagined.

Promise

Chapter One: I Promise

December 1995.

Hermione Granger emerged from the room Ron and Harry were sharing in Number 12, Grimmauld Place, feeling immeasurably relieved. When Dumbledore had told her about how depressed and withdrawn Harry had gotten after overhearing the conversation at St. Mungo's, she'd been horribly worried and was extremely glad to see him acting like his normal self now that they'd gotten the main issue out of the way.

Out on the corridor, she almost bumped into Sirius, who was traipsing along and singing "God Rest Ye, Merry Hippogriffs" at the top of his voice. She shook her head, biting back a smile.

"Hello, Sirius," she said brightly.

He stopped and blinked. "Hermione! When did you get here? Fantastic to see you, we weren't expecting you to show—but the more, the merrier is what I say!"

Hermione grinned; Sirius was clearly excitable and euphoric over the prospect of having company over the holidays. She felt a pang of sorrow and sympathy for him, trapped here in this awful house alone most of the time. She knew he'd been drinking now and then and that he had horrible mood swings. But at least, now, he was cheerful. Harry and Sirius were in a good mood—Ron and Ginny were fine—what more could she ask for?

"How is he?" Sirius asked, suddenly sobering. "Good thing you're here; he needs someone sensible like you. No offence to Ron and Ginny, but they're bloody prats acting like Harry's got the plague over the past couple days."

She couldn't help but smile at that. "He's fine now," she said, "We managed to talk some sense into him and, fortunately, he no longer thinks he's being possessed by You—I mean, Voldemort."

"Thank goodness," Sirius looked like a huge weight had been lifted off his chest. He gestured towards the stairs, and she followed him down the corridor and down the stairs, and then into the kitchen, where he proceeded to hand her some chocolate pudding left over from the previous night. Sirius leaned against the kitchen table and sighed. "I hate seeing that kid look so depressed."

"You're not the only one," said Hermione dryly, realizing she was ravenous and hungrily attacking the pudding. "I never knew what I was getting into when I became friends with Harry. It's a life of constantly worrying about him."

"Would you turn away if you had the chance?" Sirius asked curiously, watching her.

Hermione smiled wryly. "I adore Harry and Ron, Sirius. Even if I was given the chance to turn away from all this, retreat into a Muggle-born life and never have to think of them again, I wouldn't do it. Harry and Ron are more important to me than anything else. And, to be quite honest, they need me. Heaven knows where they'd be if it wasn't for me!"

He laughed. "Well, that's true enough. They're lucky, you know, Hermione, to have a friend like you. I don't just mean that because you're so clever and quick, but because you're so loyal. You remind me a little bit of Lily in that way. We'd have all been a mess—James, Remus and I—if it hadn't been for her."

She smiled at that, but felt slightly embarrassed—though also flattered—by the compliment. Hermione stared at Sirius for a minute, taking in his hollow-eyed face. She cared very much about him, ever since she had helped save his life back in their third year. It was difficult to imagine everything he had had to endure in his life—he had obviously loved James and Remus, and been very fond of Lily, and he had lost two of his best friends to Voldemort—and then, worst of all, he'd been accused of murdering them and his last best friend had believed the lies. No one could blame Lupin for that, but it had to have hurt.

Hermione didn't even want to imagine what would become of her if she lost Harry and Ron. She'd go mad, maybe, wind up in St. Mungo's jabbering about lost days. She shivered slightly.

"Hermione…" Sirius said, and his tone had changed; he sounded suddenly serious and sober.

She looked at him. "Is something the matter?"

To her surprise, he went across to the kitchen door and closed it, so that they were quite alone and couldn't be overheard. "There's something I need to ask of you," Sirius said quietly. "I understand if you refuse, but somehow, I don't think you will. I know you better than that. But it's a lot to ask." He sighed, hesitated, and continued, "I love Harry as if he was my own son, and I know, somewhere, James trusts me to watch over him. But my life isn't sure. I could be thrown back into prison at any time, if I'm caught. I could be killed in a battle with Death Eaters. No, Hermione, don't say anything—" he added, because she'd opened her mouth to protest, "—You're a realist; you know this is true. I don't know how long I'll be around here, I don't know how long I can protect and watch over Harry. But you… I know you'll do everything in your power—and that's quite a lot of power you have there—to stick around and watch over him. I just… I just need to know that there'll be someone here, someone I can trust, someone who loves Harry like I do, who will protect him if anything happens to me."

"Sirius," Hermione said, staring at him in astonishment, "Are you asking me to, if anything happens to you, fight to make sure Harry stays safe and alive? To watch over him and protect him, whatever the cost?"

Sirius sighed heavily. "I owe it to James, and I owe it to Harry, and to everyone who cares about him. If anything happens to me…"

"I'll do it."

Sirius jerked. "What?"

Hermione smiled a little sadly. "I don't like to imagine something happening to you, Sirius, because you're as much a godfather to Ron and me as you are to Harry. But I understand. Whatever I can do, however I can do it, I promise I'll watch over Harry until I have no breath left. You're right—I owe it to him too. He's saved my life enough times." She offered a flash of humour: "Would you like me to make an Unbreakable Vow?"

"That won't be necessary," Sirius said hastily, smiling, "I trust you. Thank you, Hermione. That takes a lot of weight off my mind, to know he'll be protected."

"Well, you needn't worry about that any longer. I always keep my word, and my promises."

A few months later, in some twisted kind of irony, Sirius was killed in the Department of Mysteries, and Hermione, shocked and shaken, was left with the burden of a promise her conscience and her heart would never let her break. From here on out, come rain or shine, whatever happened in Harry's life or hers, she was bound to him. She had to protect him from Voldemort, from the Death Eaters, even from himself.

She was the only one left who could really watch over him.

To Be Continued.