Notes: So, uh, I was challenged to write a Sirius/Petunia pairing and this is what my brain came up with. For the sake of the story, this is an AU where Voldemort didn't exist so that Lily and James could have a proper wedding, and Lily and Petunia at least kind of got along, but Petunia still hates magic (there was no magic at this wedding. Go with it).

A Chance to Be Wild

Sirius looked out at all the wedding guests and grinned. He couldn't believe it. His best mate was finally getting married! James and Lily had been attached at the hip for so long that they were practically married anyway, though. In Sirius' mind, this wedding was a mere formality. Still, it was a joyous occasion, and he couldn't have been more happy for the couple standing beside him at the altar.

As the priest said something about vows, Sirius' attention drifted to the bride's side of the wedding party. He frowned slightly at the sight of the maid of honor, a woman who had been conspicuously absent from all of the wedding preparations—Lily's Muggle sister, Petunia.

Petunia wasn't at all what Sirius had been expecting. She had mousy brown hair where Lily's was a vibrant red, and she had a very long, thin face. Still, she wasn't half-bad looking. Once he had a bit of alcohol in his system, Sirius thought she might be even more attractive. Good thing he was planning to get well and truly smashed at the reception.

At some point, James kissed Lily and the priest declared them man and wife. That meant that the church part was over, much to Sirius' relief. He couldn't get to the reception hall—and the alcohol—fast enough.

...

Sirius sidled up to Petunia and flashed her his most charming smile. "Hello there, I don't believe we've met."

"I'm Petunia Evans," she said, giving him an appraising look. Sirius straightened up and puffed out his chest slightly, but she didn't give away any hints as to what she was thinking. Not even a smile. Sirius was beginning to think this woman couldn't possibly be related to his best friend's now-wife. Muggle or not, there was just no way.

"I'm Sirius," he said, holding out a hand for her to shake. She didn't take it, so he quickly dropped it back to his side.

"Oh. Lily's told me about you," she sniffed.

"My reputation proceeds me?" Sirius smirked. "Look, whatever Lily said about me probably isn't true. She's not my biggest fan—"

"She said you own a flying motorbike," Petunia interrupted.

"Well, that part is true," Sirius admitted. He ran a hand through his hair and gave her a sly wink.

Rather than looking impressed, Petunia shook her head. "I don't think that sort of thing should be allowed. Magic motorbikes...what an abomination."

Sirius frowned. Lily had said that her sister wasn't particularly fond of magic, but Petunia seemed to look down on it entirely. That could foil his plans to impress her with his "magic tricks."

"Excuse me," he said, turning to grab a glass of champagne from a passing waiter. He downed it in one gulp as Petunia looked on disapprovingly. At least he now knew where Lily got those judgemental facial expressions of hers from.

...

As luck would have it, Sirius was seated right next to Petunia at dinner. He might have bemoaned that fact if he hadn't already been so drunk. Instead, he laughed. When Petunia gave him a disgruntled look, he laughed even harder.

"Oh, cheer up, love," he said brightly, patting her arm. "It could be worse."

"I doubt that," he heard Petunia mutter under her breath.

Sirius shrugged. He wasn't going to let her sour mood bring him down. His best mate had just married the love of his life, the alcohol was flowing through his veins, and the dancing hadn't even begun yet. Life was good—no, life was great.

He soon fell into conversation with Marlene McKinnon, who was sitting on his other side. Out of the corner of his eye, he could see that Petunia had struck up her own conversation with Remus, who was seated on her other side.

"I am so excited for the dancing part," he found himself telling Marlene. "I love dancing, don't you, Marls?"

Marlene gave him an odd look. "Sure, dancing's fun, I guess."

"I've got a particular dance partner in mind," he said loudly, for Petunia's benefit. "I don't know if she'll say yes, though."

Marlene rolled her eyes. "Something tells me you'd like me to ask who that someone is."

Marlene was really quite clever, Sirius mused. That was exactly what he had wanted her to do. Petunia seemed to be shooting furtive glances over at him, which was precisely what he had wanted her to do as well. He wanted to make sure that she heard his next words.

"I can't be too specific," he drawled, slinging an arm around a bewildered Marlene's shoulders, "but she's very pretty and very single...and she's sitting at this table."

Marlene scoffed. "Good, it's not me." She was happily in a relationship with Benjy Fenwick.

Petunia, Sirius noticed, was blushing slightly, but carried on talking to Remus as though she wasn't. He grinned. Now that the seeds had been planted, hopefully she would be amenable to the idea when it came time to dance.

...

Sirius loved a good challenge, but Petunia Evans was proving to be a very, very difficult one.

"I don't want to dance with you, Sirius," she said flatly, arms folded across her chest.

Sirius wildly offered the next thing that came to mind: "Maybe you'd like to ride my motorbike, then?"

Her expression, normally so carefully guarded, changed. Her eyes widened and her cheeks flooded with pink.

"Your bike?" she stammered. "Oh, no, I couldn't possibly..."

Sirius knew weakening resolve when he saw it. After all, he had watched Lily warm up to James, and this wasn't that much different, really.

"Come on," he wheedled. "You'll have fun, I promise. I'll make sure of it, in fact."

"Alright, fine," Petunia relented. To Sirius' surprise, she began to giggle like a schoolgirl reading her first naughty magazine. "Don't tell Lily!"

Sirius gulped. He was absolutely, under no circumstances, going to tell Lily that he was taking her sister on his motorbike. She would probably hex him into next week if she knew, and he definitely did not want that.

"Don't worry," he said hastily. "She'll never have to find out."

...

"So how come you agreed to ride this thing?" Sirius asked, strapping his helmet onto his head.

Petunia shrugged and began to put on her own helmet. "I guess I just liked the idea of being a little wild. Lily says I'm too uptight, and I realized I would probably never get this chance again, so...I said yes." She eyed the bike dubiously and shook her head. "I think I'm beginning to regret it, though."

"You'll be perfectly safe, love," Sirius assured her. "Do you trust me?"

"I shouldn't," she said with a sigh, "but I do."

"Just grab my waist and hold on tight, then."

She slid onto the bike behind him and, after a moment's hesitation, circled her arms around his midsection.

"Ready?" Sirius turned the key in the ignition and prepared to kick off.

"I'll have you know, I'm scared to death," she whispered, increasing the pressure around his waist. He imagined that she probably had her eyes closed, and chuckled a little at the thought. "But...yes. Yes, I'm read—"

The rest of her sentence turned into a shriek as the bike lifted off the ground. Sirius chuckled.

"It's alright, I've got you." He turned around and smiled. "I won't let anything hurt you."

...

When they touched back down, windswept and pink-cheeked, Sirius grinned. "What'd you think?"

He helped Petunia down from the bike, then bounced on the balls of his feet as he awaited her reply.

"That was…" Petunia seemed unable to speak for a moment. "It was amazing," she said at last. "The feel of the wind rushing past, the way everything looked so inconsequential from those heights...oh, Sirius, I wish we could have stayed up there forever."

"I wish we could have too," Sirius agreed softly.

Petunia took a step towards him. "I had fun tonight."

Sirius knew, even in his alcohol-buzzed brain, what she was trying to tell him. He also knew that it was probably a bad idea. She was a Muggle, and Lily's sister, to boot. But he was Sirius Black, king of bad ideas, so he ignored the little voice inside his head and kissed her.

Her lips were cold from their aerial excursion, but Sirius didn't care. He eagerly wrapped his arms around her waist and tugged her closer. All the while, that little voice was screaming that this was the worst idea he had ever followed through on. It couldn't be so wrong when it felt so right, though.

He finally pulled away, giving her an apologetic look when she protested. "We should really get back to the party before Lily or James notices we're gone."

She agreed with that, and when the two reentered the reception hall, they barely looked at each other for the rest of the night.

...

"Black!" Lily shouted, stalking towards Sirius with an angry look on her face. "What's this about you kissing my sister?"

A week had gone by since the wedding, and Sirius had assumed that Petunia had kept up her end of the bargain and not told Lily about the bike ride. It seemed, however, that she had not kept their other activity a secret.

He pasted an innocent look on his face. "I don't know what you're talking about, Lily."

"Cut the crap," she hissed. "I can't believe you would—would use her like that!"

"I wasn't using her!" Sirius said indignantly. "She wanted me to kiss her!"

Lily gave him a triumphant smirk, and he quickly realized his mistake. Before he could backtrack, however, her expression turned irate once more. "It was still completely irresponsible of you!"

"Honestly, Lily, I think you're blowing this way out of proportion," Sirius said cheerfully. "Your sister is a grown woman, I am a grown man—"

"I have my doubts about that second part," Lily muttered.

"—and we both consented to the kiss, therefore, I see no problem," Sirius finished. He was quite proud of his little argument, though Lily, it seemed, was not impressed.

"It can't happen again," she warned.

"It won't," Sirius said, exasperated. "It was just a fluke thing, you know?"

Truthfully, he would have liked to see Petunia again—he wanted to nurture that rebellious streak in her—but he didn't fancy crossing Lily like that. She was more than capable of making his life miserable, and James would probably never forgive him, either.

James himself poked his head into the living room a moment later. "Everything alright in here? I thought I heard shouting."

"Yeah, all good, mate," Sirius said, flinging himself onto the couch. "Just having a nice little chat with the wonderful Mrs. Potter."

Lily rolled her eyes, but at least she didn't look mad anymore. Sirius smiled to himself. Petunia was more like her sister than he had originally thought—he could see glimpses of her even in Lily's irritation, and he wondered what other ways the two women might be similar. He would just have to observe and find out.

WC: 1,842