Title: This is Our Life
Author: SorryGrimmjow
Genre: Romance, Angst, Crossover
Rating: M
Pairings: Remus Lupin & Sirius Black, background James Potter & Lily Evans
Summary: When Sirius Black joins Fight Club, he gets more meaning and energy out of life. He also meets someone new, someone special: Remus Lupin. But when Fight Club becomes more than they had ever dreamed, Sirius and Remus struggle to get out before it becomes too dangerous.
Disclaimers: The wonderful world of Harry Potter is not at all mine and obviously belongs to the brilliant J. K. Rowling. The plot, however, is mine.
Warnings: Language and mild sexual content.
Notes: Title based off quote in Fight Club: "This is your life, and it's ending one minute at a time"

One

The infrequent lights flickered past him at uneven points, the cold wind whipping past his free, dark hair. It really was a bad part of town, Sirius noted. It was desolate, kind of creepy even. But in the heart of this dark, quiet, place, fights raged on underground and Sirius craved them.

The first time he went to Fight Club was an accident. He had been hanging around a bar, getting drunk, trying to forget his worries. But he found something much better than alcohol. When he staggered outside a few minutes before closing time, he overheard some burly guys speaking to one another.

"You sure this is even real?" one of them had said.

One of his companions nodded although he didn't look entirely convinced himself. "We can just check it out. If it's not we can go home."

"I'm hoping you're right," the third guy said, taking a deep drag from his cigarette before throwing it to the ground, "Even though this Fight Club is probably bullshit."

Fight Club? Sirius watched the three guys disappear through the doors of the bar hazily out of the corner of his eye before pushing himself off the wall to follow them. His curiosity, as usual, got the better of him.

The smoke still infested the air but the music had been turned down. The barman was attempting to rid the place of people to no avail. Sirius caught sight of the three men that were outside easily and followed them at a discreet distance. He waited for the three of them to depart down some stairs and into the basement after a bit of bickering before walking down himself.

Now Sirius was cautious, for he had no idea what he was doing here or what the other guys were doing here, but there were a lot of them. Men crowded the basement and it smelled of sweat and blood. The air felt wet there was so much of it, so many men sweating and breathing and panting. Sirius' breath hitched as he came down the stairs and realized that all of these men were shirtless and barefoot, crowded around a single guy. Why, though, he could not figure out, because the single guy looked a bit weak physically. He had short hair, sunken eyes with ridiculous bags underneath them, and a discolored, limp cheek. But his voice held a no-nonsense tone and the way he held himself was nothing less than bold.

No one seemed to notice Sirius as he moved closer towards the donut-shaped formation of men, and he redirected his attention so he could hear what the guy in the middle was saying.

"The first rule of Fight Club is you do not talk about Fight Club."

The guy yelled out six rules that followed the first. Sirius was confused and somewhat frightened, but decided that he would stay. Determination and craving and hunger for power hung heavy in the air and Sirius wanted to know why.

And then the fighting began. Two men to a fight, just as the rules said. One fight at a time, just as the rules said. No shirts, no shoes, just as the rules said. Sirius watched the two guys take blows from one another. Deep grunts of pain were barely heard over the yelling and calling and roaring of the crowd that surrounded them. The single guy that was in the center, the leader, was circling around the outer area and Sirius stiffened as he grew close. The leader seemed to take notice of Sirius and the pumping of his blood and awe but didn't do anything. Not yet.

One of the guys in the center tapped out. The floor had blood mingled with sweat rubbed across it. The guy who had tapped out limped over and fitted himself into the crowd just diagonal to Sirius.

"You're new; fight!"

Before Sirius knew what was happening, he was pushed forth. Another guy who looked just as scared as he felt was also pushed into the center of the circle.

"No shirts, no shoes!"

Sirius scrambled to shrug off his leather jacket and throw it towards a wall, his white shirt following it. He then toed off his black combat boots and kicked them to the side. And there he stood, just in his tight, dark denim jeans and sweat and anticipation. Sirius moved his gaze towards the other guy who he was supposed to fight against. His jaw was tight and eyes set on Sirius, just as shirtless and barefoot as he was. And then they charged.

It was incredibly awkward at first. Sirius didn't know where to punch, how to duck. The other guy seemed just as inexperienced and the two circled each other uncertainly, hands far too high up, trying to guard their scared faces.

His opponent then threw a punch at an awkward angle and caught Sirius to the left of his chin, his fist halfway in the air. The knuckles that connected with Sirius' flesh made a sickening sound and Sirius gave a small hiss in surprise. His opponent dropped his hand while Sirius stepped back, rubbing at his chin. It was…the strangest thing.

It was as if a spark had ignited in his mind, telling him to fight because it felt right to defend his own body. To hurt one another. To destroy them, after being slowly destroyed himself. It was time to return the damage, although it wasn't the source of it, he would be letting it out. Letting it go.

Sirius gave a toothy smile before winding up in order to punch his opponent's cheek. Caught by surprise, the opponent gave a small yelp before looking up to meet Sirius' grey eyes with his own.

This was good.

By the end of this meeting of Fight Club, Sirius was bloody, tired, sweaty, panting, and he had never felt so alive. He found his shirt, jacket, and boots that were left on the floor; they quickly became damp as he pulled them over his sweaty body. His dark hair stuck to his face and his mouth tasted of blood. He found the guy who he had fought and told him that it was a good fight.

The two continued talking casually as they walked up the stairs and departed the now dark bar.

"What is this, anyway?" Sirius had asked as he pushed open the door and stepped out into the otherwise empty parking lot.

"What?" the guy asked simply, fishing out his keys from his pocket.

"Fight Club."

"What?" he repeated with a smirk, opening the door of his car and sliding in.

He gave a short wave through the open window before driving off, leaving Sirius in the clearing parking lot.

Since then, Sirius had been hooked. He could drive off unwanted energy, be surrounded by new energy, and get lost in the fights and roars and blood and sweat. He looked forward to it always; he never missed a fight in the old basement of that smoky bar.

Sirius parked his motorbike in the parking lot of the bar and slid off it easily, stuffing his keys into his leather jacket. He went inside and headed straight for the door to the stairs to the basement. His body could sense the excitement that raged on down on this level. The smell of blood and sweat hung heavy in the air as always, and the room was thick with shirtless men. Sirius shrugged off his jacket, shirt, and boots before joined the men circled around the main man.

He had learned between his first fight and now that this guy's name was Tyler Durden. He created Fight Club. He started it, made the rules, and kept it alive. He was the heart of Fight Club, and it just continued to branch into something brilliant.

Sirius was excited to fight. He had waited for this and wanted it fiercely. He edged through the crowd to get to the front. Hands already curled into tough fists, eyes not watching the fight in front of him, but scanning the other men across from him for a worthy opponent. Ah.

He looked perfect. Thin and uncertain he was, but there was something completely different about him as well. Scars covered his chest and torso, like some sick patterning of his flesh. Although his man had a weak demeanor, the scars gave him some sort of mystery and strength. His light brown hair hung in his matching eyes, still dry. He was not bloodied, or sweating, and he was perfect.

Sirius grinned in anticipation, and waited impatiently for the fight to end so he could begin. Finally, one of the fighting men had tapped out after having his nose broken and probably some ribs too. Sirius strode boldly into the center of the circle and eyed the man he had previously spotted.

"You," he said neither loudly nor softly, but pointed at him, staring him down hungrily. "I'm fighting you."

The light-haired guy's eyes widened a bit, as if uncertain that Sirius had chosen him, but a moment later he staggered forward, assuming a fighting stance. Sirius bit down a grin and positioned himself as well, weight on his back, curious as to see how this mysterious individual would fight.

"Fight!" said a voice, and Sirius swung.

The guy dodged down gracefully, to Sirius' surprise. He didn't have time to be, however, for the fair-haired man gave Sirius a sharp uppercut as he came back up. Sirius winced, rubbing at his jaw with a hand, the other serving as his only defense. The guy smiled a crooked smile, and Sirius stopped rubbing and focused.

The fight lasted longer than he had thought it would, though Sirius did win by the end of it. The scarred man wasn't hurt too badly and seemed to bear no ill will towards Sirius. Sirius nodded at the end of it, keeping strong eye contact and backed away into the roaring crowd once more. He felt the man's eyes on him even after the next fight started.

At the end of the session, Sirius went over to the wall to pull his clothing back over his sweaty body. As he shrugged on his dark jacket, his eyes racked through the room to find the scarred man he had fought with earlier that night. Sirius found him by the other wall, clothing himself as well. Sirius rushed to put on his boots and caught the guy about to go up the steps. He looked slightly surprised to see him, but intrigued all the same.

"Your first fight, huh?" asked Sirius, trying to keep his eyes on the steps below him instead of on him. Didn't need to creep the guy out that much.

The man nodded, so Sirius asked how it was, turning grey eyes on him. He fought back to silence the small intake of breath when he finally got a good, close look at him when they weren't challenging and punching and bloodying each other. The guy was good-looking, but not in the way Sirius normally thought of. He saw now that scars lined his face as they had lined his chest, but that did nothing to distract from those light brown eyes that looked so intense and knowing. It made Sirius uncomfortable, so he looked back to the steps. Jesus, he was hornier than he would have liked to admit.

"It was…interesting," said the guy after a moment. "New and alluring. Certainly thought-provoking and it was a nice change of pace to my day-to-day lifestyle. I suppose I'll come back next time."

"Erm," Sirius said dully, who had turned to look at this guy in disbelief. "That's great," he cleared his throat. Tried not to sound thick. He said teasingly, "Just don't break the first rule."

"Ah, right."

Who the fuck talked like this? Who the fuck had that sort of soft tone that still showed that he wasn't some sort of shy idiot?

The two made their way through the bar in silence, though it wasn't terribly uncomfortable. When their gazes met the parking lot, they stopped and turned toward each other in the dim night.

"I guess I'll see you next time then," Sirius said, inwardly cringing at his lack of creating good conversation with this individual.

"I hope so," said he, his lips quirking upward. "What's your name? I don't believe I caught it."

"Sorry; must've slipped my mind. Sirius," he said, extending a hand. Not wanting to give his surname, as it held false meaning.

"How peculiar. Remus Lupin," said Remus Lupin, shaking Sirius' hand. Firm, but gentle enough.

"What's peculiar?" asked Sirius as his hand dropped limply to his side. He hoped it wasn't the fact that Sirius only told him his first name.

"Your name," Remus said, though not unkindly. "I've never heard of someone called Sirius before."

Sirius snorted. "Says the guy named Remus Lupin."

"Fair enough," Remus looked him over one last time before nodding briskly, a slight half-smile on his face. "It was good meeting you, Sirius. I will see you soon."

"Yeah."

As Remus walked away into the night, Sirius noticed that his neck had grown hot sometime during the exchange. He remembered how Remus' all-seeing eyes had run him up and down and shivered slightly. Disciplining himself that he shouldn't be going to Fight Club to meet fit guys, he walked over to his motorbike and fished out his keys. As he flung his leg over the bike, he gathered that he didn't go to Fight Club just for that. It also helped to blow off steam.

But it was nice to meet fit guys.

Author's Note: i started this when i was in my major fight club obsession and i guess i'm still going through with it
this is also my first au so please don't be too harsh okay xoxo
reviews are always really appreciated!
also ps expect slow updates sorry i'm a lazier person than i was six months ago
oh pps the writing style will probably change drastically and abruptly since at first i was all FIGHT CLUB ! but then it was a while since i read the book so the style isn't so much as palahniuk's it's more mine i guess which i think might be a little weird with fight club but ssh
damn ppps they're supposed to be american in this story which i know is really weird but i wanted tyler durden/the narrator in it since i love him so much