For Lolaaaa's Last Kiss Competition on the Harry Potter Fanfiction Challenges Forum.

Summary: "I know what it feels like to live without you. And I don't ever want to go back to that." Remus/Sirius, the day before the battle of the Department of Mysteries.

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"You Aren't Invincible"

The firelight flickers, orange fingers almost licking the soot covered chimney flue. A faint smile crosses a peaceful face, stretching muscles too long underused. Remus smiles in return, tucking a finger in the spine of his book to mark his place and glancing up at Sirius. He's been lying on the couch, using Sirius's leg as a pillow. It's a strange habit, but one that both of them have picked up in the last two years – since Remus understood Sirius's innocence. After spending almost thirteen years apart, neither of them ever want to be separated again, and physical contact is just an infallible way of knowing the other is there.

"Good book?" Sirius asks softly. Remus flips it so that Sirius can see the cover. The Extensive Uses of Defensive Spells – and Their Fallibility. "Charming," Sirius says dryly. "Sounds like a cheerful read."

Remus grins softly. "Very much so," he retorts swiftly.

The corners of Sirius's mouth turn up ever-so-slightly, as they always do when Remus is sarcastic. Given their proximity and familiarity, though, Remus can't avoid seeing the darkness in his silvery-grey eyes. Sirius doesn't often smile with his eyes anymore.

He doesn't say anything, though, and he won't. Remus learned in their first year that if Sirius wanted to talk about something, he'd bring it up himself, and if he didn't, he wouldn't. It was best, in such cases, to let the issue alone.

Remus shifts, though, so that he's sitting up properly. He reaches out a hand as though to initiate contact, but then withdraws it. Something sparks in the unfathomable grey depths.

The hardest thing about all of this, Remus thinks, is that it's almost as though they've regressed. They've almost returned to that awkward stage when they were both sixteen and confused. They've had to relearn each other, what it is to spend nearly every waking moment with the other.

There are some things, of course, that are still completely intuitive for the both of them. When he gets up in the morning, Remus automatically turns on the little Muggle coffee maker when he puts the kettle on for tea, because Sirius, despite being raised in a tea family, is a coffee drinker. Black, of course, which has been the root of quite a few puns over the years. He still, whenever Sirius lays next to him, runs absentminded fingers through Sirius's hair – a comfort that Sirius picked up from his Animagus form, Remus thinks.

And Sirius, too, fell quickly back into the habit of drawing up a bath ten hours after moonset on the day after a full moon – because Remus always sleeps that long, and it helps. Sirius hasn't forgotten any of the spells Madam Pomfrey taught him so many years ago; the few spells that can heal a cursed wound, if not completely. And Padfoot still sleeps curled up against Remus's side immediately after the transformation back, without Remus ever having to ask, because the contact – even canine contact – makes him feel more human, because the sensation is human rather than animalistic.

They haven't forgotten how to live in sync, but it isn't all the same. Sirius didn't used to wake up screaming weekly. Remus didn't used to doubt everything, unable to trust. Sirius didn't used to flinch away from contact when he didn't register that it was Remus quickly enough.

It all used to be so uncomplicated. They still fit together like puzzle pieces, but not quite so perfectly – now it requires just a little bit of effort for things to go as smoothly as they used to.

And that's almost harder, for how effortless it used to be.

And just as Sirius's hand twitches to take Remus's, a streamlined, silvery wildcat slips into the room.

"Remus," the lynx says hurriedly. "Potter's in the Department of Mysteries. Now."

Both men bolt upright abruptly at Kingsley's words.

"Harry," Sirius breathes, panic-stricken. He leaps up, grabbing his cloak and bolting for the door. Remus catches his arm before he can even exit the room.

"Sirius." It's all he has to say. Sirius turns to meet his eyes. Remus is looking at Sirius, his amber eyes burning, and Sirius knows the look. It's Remus's Sirius-don't-you-dare-run-off-and-do-something-else-stupid look.

"But…" Sirius begins to protest, but he knows Remus is right. Rushing into things – his specialty – tends to have disastrous results.

Remus calmly picks up his own cloak, but he's not looking at Sirius, he can't look at Sirius, as he says, "I don't think you should go."

Fury blazes in Sirius's eyes, turning steel into molten silver. "What?" His voice is cold as ice, a sharp contrast to the fire in his eyes.

Remus glances up at him. "I don't think you should." He lowers his gaze. "What if you get caught?" Remus hates the way his voice cracks on the end of the sentence. He hates himself for sounding so vulnerable.

"I thought you understood, Rem. Staying penned in here is killing me." Sirius is deadly serious.

Still unable to meet his eyes, Remus murmurs, "I know."

"Then…" And Sirius doesn't even need to finish the question.

"Because I don't want to lose you." Finally, Remus lifts his gaze to Sirius's stormy eyes. "I can't. Not again."

And this, Sirius understands. He takes a step toward Remus, lifting a hand and settling it on Remus's cheek. "You won't. I promise."

"You can't promise that," Remus whispers.

Sirius can't stop the small smirk that crosses his face as he drops his hand and says, "You think I'm going to let a Death Eater take me down? Give me some credit."

Remus is whispering now, almost afraid that saying it makes it real. "You aren't invincible, Sirius."

Sirius lowers his gaze, unusually sober. "I know that."

"Do you?" Remus asks.

"You worry too much."

"I just… Sirius, without you… I survived, but it wasn't… And I know it's nothing like what you went through, but it's different, because I know. I know what it feels like to live without you. And I don't ever want to go back to that."

"You won't have to. I won't let that happen."

Softly shaking his head, Remus murmurs, "You can't promise that, you fool." But he's smiling, and there's no malice in his voice.

And suddenly, Remus crashes their lips together. The years between them, the doubt, the guilt, the pain, it all vanishes, and it's like they're sixteen again and nothing in the world matters but them.

When he pulls away slightly at last, Remus whispers, "Just don't do anything stupid, okay?"

And, smiling, Sirius murmurs in return, "Only for you."