#rbi

She was in Sirius’ year, but her parents were part of the noble society so both Regulus and Sirius had known her since she was a young girl. They were never really in the same circle, but Regulus would be happy to talk to her if he had to. 

He almost did a double take one night when he was downstairs getting a glass of water and she came tiptoeing down the stairs. 

A look of horror struck her face as Regulus brought the glass away from his mouth and said, “Hi,” in a cheerful manner as if this wasn’t weird at all. 

She had her shoes in one hand and a sparkly bag in the other. Her hair was frizzy, her lipstick was smudged and her mascara was running. 

She stood in front of him frozen, trying to pull her short dress down as she repeated the greeting to Regulus. 

Regulus was confused. He knew whoever Sirius got with was usually someone who would make his parents upset if they were ever around to see it happening. But Regulus thought that if his parents found out Sirius was seeing her, they wouldn’t be able to find anything wrong with it. 

“Uhm,” she said, clearing her throat, “how have you been?”Regulus found it humorous that she was trying to make a conversation right now, but Regulus decided to go with it. 

“Great, I haven’t seen you in ages, how’s work?” 

“Great,” she exclaimed, “I love it, I mean I miss Hogwarts but it’s so much fun to be out in the real world don’t you think?” 

Regulus had been ‘out in the real world’ for just over a year now and she had been out for two. They had definitely seen each other since at all the formal events both of their families attended, but they had never had a proper conversation. 

“It is,” Regulus agreed, starting to talk about how nice it was to have freedom before he heard footsteps coming closer to them. 

Both of their heads turned around to Sirius Black, confident in his grey tracksuit pants and bare chest as he rolled his eyes. 

“Shouldn’t you be home by now?” Regulus knew that his brother was never a doting ‘hookup’, but he was taken aback by how he spoke to the girl they had known their whole life. 

“Well if you had just let me apparate in your room I would have been gone by now,” she said through gritted teeth. 

Sirius rolled his eyes as he pushed past her to also get a glass of water. 

“Well,” she said, rolling her eyes straight back at him, “it was nice to talk to you, Regulus.” And with that, she apparated on the spot. 

Sirius knew she had done that just to piss him off. He wasn’t sure why he wouldn’t let her apparate in his room. None of the muggle girls did so why should she? And maybe, a part of him also knew that she would hate walking out trying to stay quiet so Regulus wouldn’t see her, and he wanted to make her do that. 

“So,” Regulus started awkwardly. “She’s not a muggle.” 

Sirius scowled at him. 

“Keep your nose out of it.” 

Regulus shrugged. 

He was happy with that. 

The less he knew about his brother’s love life, the happier he was and he wasn’t going to push it. 

He didn’t say anything else, just finished his water, gave it a quick wash and went back up to his room. 

Their parents were overseas for the next six weeks so it was just the two of them in the big house. 

Regulus had thought about bringing a girl back here. If Sirius could do it, so could he. And there had been few occasions where he had brought a girl back, but Regulus wasn’t into hookup culture at all. 

He couldn’t understand how Sirius brought a different girl back every weekend just to never see them again, but he knew that was what Sirius liked which was why it was so strange when two weeks later he heard her voice again. 

Usually Sirius used the silencing charm for his room, but he must not have been quick enough because when Regulus was going to the bathroom he could hear her yell. 

“You are such an asshole Sirius Black.”

“Then go find someone else,” he heard his brother yell back. “Go on,” he continued. “Don’t think I can’t find another fuck, I’ll get someone here before the time you apparate.” 

Regulus didn’t mean to eavesdrop and if he was being honest, he really didn’t want to hear this conversation, but it was like watching a car crash. He couldn’t find it in himself to turn the other way. 

“And you don’t think I can do the same?”

“I’m sure you can do the same,” Sirius scoffed, “you’ll put out for anything with a pulse.”

“Says you,” she spat back. 

Sirius grumbled something under his breath that Regulus couldn’t make out. Regulus, who was frozen stiff on the spot. How could he move? And how could he ever face her again? Regulus was appalled by the way his brother spoke to the girl they had grown up with, but Regulus couldn’t say he was surprised. 

“You’re the biggest fucking brat I know,” he heard Sirius say. Then he heard a loud whimper. “Always fucking arguing with me, how about we put that mouth to better use.” And then he heard her gasp. 

That was when a wave of sense rushed over Regulus and he walked all the way back to his room. 

He wasn’t sure he would ever be able to look at her the same ever again. That was why he waited until the next morning to leave his room even if he had a strong incline that his brother wasn’t going to let her stay the night. 

The next time he saw her was at a celebration before Christmas. She came in with a boy on her arm that they had gone to school with. He was in Slytherin in her year and Regulus was trying desperately hard to remember his name. 

He wasn’t sure he would be able to say hello to her, but he did, briefly, and then walked the other way. 

He felt bad, but all he could hear was her whimper and the noise she had made when–

He shivered. He was not going to think about it. 

To distract himself from it, he looked around the room, trying to spot who he could go and strike up a conversation with. 

Instead, his eyes landed on his brother and the girl he was just trying not to think of. They were arguing in the corner. At least, he thought they were arguing. Sirius was bent down to her height and their faces were inches apart. Regulus could see the vein prominent on Sirius’ neck from the otherside of the room. 

Knowing his brother, he was probably upset that she had brought someone tonight. It was all too predictable. Especially when he grabbed onto her arm and pulled her out of the room. Regulus' eyes instinctively searched for her boyfriend who was talking to Evan Rosier in the corner. 

Regulus wasn’t sure why, but he kept his eye on him to make sure that he was preoccupied until her and his brother walked back in. Both of their hair a mess and a fresh new layer of lipstick coating her lips. 

There was a part of Regulus that wanted to go over there and talk some sense into them. They were acting immature and she was being unfaithful. 

But Regulus did not want to get involved so he stole a champagne flute from the waiter and sculled it down. 

He wanted to say that he was surprised that night when she came back home with Sirius. Regulus saw them apparate away together and he also saw the wink Srius shot him as if he was in on whatever it was that Sirius was doing. 

But Regulus wasn’t in on it and he didn’t want to be in on it. 

He knew they had some weird relationship going on and he had a weird feeling that she was one of the only girls Sirius Black had brought back to Grimmauld Place more than once. And he knew that she was over at least once a month, but both of them were still seeing other people, and that was all he wanted to know. 

He was already in far too deep anyway. 

This was why he was cursing the universe when she came over on a random Wednesday afternoon and knocked on the door. 

Regulus found it odd that someone was knocking on their door. Their parents were overseas once more and neither Regulus nor Sirius had had any visitors who had knocked while their parents were away. 

But when he opened the door she was standing there in a very short skirt and a very tight top that made Regulus’ body go stiff. 

“Hi,” she said sweetly. 

“Hey,” Regulus said, his voice coming out in a weird way that made him clear his throat. 

“Is Sirius here?” She asked as if she didn’t know the answer. 

Of course she knew the answer. She knew that Sirius worked on Wednesday’s and didn’t come back until 3.30. But she also knew that Regulus had every second Wednesday off which was why she had showed up at exactly three. This had to be timed perfectly. 

“He isn’t.” Regulus said. 

“Oh,” she pouted, “will he be long?” 

“I think he finishes work in about half an hour.” 

“Do you mind if I wait?” 

She knew that Regulus wouldn’t be able to say no. Maybe the eldest Black brother treated her like shit, but she knew Regulus had a bit more respect. 

“Not at all.” He welcomed her in and she smiled as she sheepishly took a step forward. 

It was in their seventh year that Sirius had started to become comfortable as a philanderer. It wasn’t until their last month that she first hooked up with him. 

They were both very drunk at a party in the Ravenclaw common room when Sirius came up to her and said, “You know, I’ve always thought you’d be a good fuck,” like the true gentleman he was. And before she knew it, she was in the bathroom with Sirius’ fingers working skillfully against her spongy walls while she bit into his shoulder, trying not to draw attention to their situation. 

She should have said goodbye to him when he pulled out just before her body was able to let out the release he had been building up. He chuckled and pulled her panties up, giving her clothed slit a tiny pat. 

She was dumbstruck as he held onto her cheeks between his thumb and forefinger. 

“Did you really think I’d let you cum without you even touching me?” He chuckled at the way her mouth rested open, unable to form a response. “Come see me later tonight and maybe I’ll think about it.” 

She blamed the fact that he left her hot and bothered for the reason she followed him into the room of requirement that night. But she wasn’t sure what she was blaming it on when even after Hogwarts, she kept seeing him to do unspeakable things. 

Especially when he treated her so poorly. 

She’d go out with her friends and see Sirius with his and as soon as he saw her there he was going and finding another girl that ended up grinding on him while he was basically groping her all while keeping eye contact with her the entire time. 

But as soon as she was within centimetres of another guy, he’d get jealous and instantly go to slut shaming her. 

He wasn’t sure why he kept going back to her. He thinks it is because he likes that she always fights back. 

He’ll tell her that she’s a slut because apparently it seems like she’ll open her legs for anyone and then that night she’s keeping her legs crossed until Sirius manhandles her and ties them apart so she can’t close them. 

Or she’ll tell him that he’s one to talk when he has a different girl every night and he’ll say that’s so she knows she’s easily replaceable, so she’ll say that she’s never going to have sex with him again, and he’ll laugh because he knows as soon as he tugs on her hair and calls her a brat, she’ll do anything he says. 

So they’ve been on and off like this since then and she knows she should stop, but for some reason there’s just something that keeps calling her back and she knows it is hidden in Sirius’ pants between his legs, but she’ll never admit it. 

But yesterday, they had a big fight. 

And for the most part, it was one of their usual grievances, but for some reason there was something that clicked inside of her. 

She had gone back to his after a night out with their friends and Sirius was mad because she let someone buy her a drink. 

“Well it’s not like you ever buy me a drink.” She spat, the effects of said drink long gone. 

“That’s not the fucking point,” he growed, tugging at his hair. 

“Then what’s the fucking point? It was just a fucking drink.” 

“You were sending signals to him.” 

“Signals?” She screeched. “What, are you twelve? I accepted a drink from him, you're making something out of nothing.”

“Don’t pin this on me, you were basically inviting him to fuck you right there.” They were facing the other, their faces close together as they didn’t even attempt to keep their voice down. 

“Says you,” she basically spat at him, “everytime I see you out you’re groping a random girl.” 

“Aww,” he cooed mockingly, “does that make you jealous?”

“Why would it make me jealous, Sirius?” She taunted. “If you didn’t drag me here I would’ve gone home with the guy who bought me a drink.” 

It was a swift movement that she had gotten used to. Sirius’ hands found her hips and he twisted her around so her back was on his chest and as he moved her he grabbed on to her hair to pull it back so she was looking up at him. 

“You’re a fucking brat.” He growled in her ear. Sirius already knew something was wrong because whenever he did this it usually resulted in a whimper. But this time she didn’t make a noise which was why Sirius loosened his grip enough for her to slip out. 

“Not this time Sirius.” She said, her voice much softer than what it had just been. “You can’t just treat me like this and then expect a fuck.” 

“Fine.” Sirius said, trying not to act like he was humiliated. “Go home and get yourself off with those useless fingers of yours, but don’t come back here expecting me to help.” 

“Don’t worry,” she said, a sly look in her eye, “the guy from the bar gave me his address.”

“Fuck you,” he swore as she made the move to apparate. “You’ll be back here by the end of the week you always pull this shit you-” he was talking very fast in hopes she’d hear his final word, but she had apparated before he got to finish. 

There was always a piece of her dignity that she lost whenever they fought and she’d swear that Sirius was wrong because she was never coming back only to show up two days later ready for a fuck. 

But she wasn’t going to let that happen this time. 

This time, she would be back, but not for Sirius. 

Regulus led the way to the living room and she sat herself on one of the lounges. Regulus copied her. 

There were many things that could go wrong with this plan and all she could really do was hope that the universe would work with her because she needed this to go right. 

Her lips were in a pretty pout as she let a small sigh escape her lips. 

“Are you okay?” Regulus asked, a small worry line etched between his eyebrows. 

“Yeah,” she sighed. 

Regulus was appalled by the question that he followed up with. “Is it Sirius?” He already knew the answer to that one and he did not need any information but the intended ‘yes’ he knew would leave her lips. 

“I don’t want to start anything.” She went with instead, even though she had already done just that. 

“It’s okay,” Regulus said, “I know what he’s like.”

He wasn’t entirely sure why he was having this conversation with her. He had vowed not to get entangled in Sirius’ love life, and here he was, doing just that. 

She turned her body to face him and when her short skirt shifted to expose the tops of her soft thighs, Regulus had a pretty good idea as to why his brain had forgotten everything he had promised himself he wouldn’t do. 

“He’s so mean to me sometimes,” she pouted. Sure, she needed to put on a bit of a show to get her plan to work, but this was the easy part because really, this was no lie. 

Regulus knew that in the short time she had walked in through the door, he was in too deep, and when she looked up at him with her glossy eyes he figured that there was no point trying to get out when he was already so far down. 

“We got into a fight,” she continued. “And he said some really mean things.” 

For some reason, Regulus was hanging on to her every word. 

“I’m sorry.” 

She didn’t acknowledge what he had said. 

“He always says I’d put out for anything with a pulse,” she grumbled, “dickhead.” Maybe he hadn’t said those words exactly during their last fight, but she needed to word this exactly right. “I don’t want to see him anymore, I think I could do better, what do you think Regulus?” She said it quickly and moved her body again to Regulus so this time all he could focus on was the slow rise and fall of her chest that was bare above the thin top she was wearing. 

Regulus cleared his throat, trying to sound as normal as he could, “I think you could do better.” Because he did. He truly thought she could do better. 

“I wish someone would just help me take my mind off him, you know?” 

“Sure.”

“I haven’t been with anyone since I’ve been with Sirius and I know he’s been with other people,” she scoffed, “and there’s just a part of me that wants to get even with him, you know?” 

Regulus didn’t say anything. When he first saw her standing outside Grimmauld Place he had thought that her outfit was for Sirius, but since the time Regulus had spoken last, she had somehow moved closer to him on the lounge and Regulus wasn’t so sure what he knew anymore. 

“I probably sound like an idiot,” she said quickly, “I’m sorry, Regulus, I’m going to blame your brother for the way I’m acting, but-”

“It’s fine.” Regulus said, his hand instinctively going to rest on top of hers. 

She smiled innocently up at him. 

“I know what Sirius is like,” he repeated. There was a small silence as Regulus contemplated what he was going to say next. Regulus wasn’t as busy with girls like his brother was, but Regulus didn’t think he was a complete idiot for thinking that she had come here for him. “If you like,” he paused, “I can help you take your mind off him?”

It took everything in her body not to react to his statement. For a second, she was a little concerned that Regulus wasn’t going to give in to her advances and she’d have to leave looking like a fool. 

“Really?” She hoped Regulus couldn’t hear how loud her heart was beating as she sat up at his question. 

“Sure,” Regulus shrugged. 

For a second she wondered if maybe there was a communication error, because Regulus didn’t make a move and she was so used to Sirius calling all of the shots that she was admittedly lacking in that department. 

She was looking at Regulus expectantly, waiting for him to call the next move, and finally, he leaned in closer to her. 

“I’d treat you much better than Sirius,” he whispered and it was fair to say that the statement shocked both of them. 

She always thought both Black brothers were quite attractive. If it was Regulus who she had become acquainted with that night at Hogwarts she would have done everything the exact same. 

And Regulus couldn’t deny that she was attractive. And maybe there was a reason Regulus didn’t want to get involved in Sirius’ love life considering the one girl he kept going back to was the one that Regulus liked most. 

“Show me, then.” She whispered back and that was all it took before Regulus’ lips were on hers. 

There was a brief flash of guilt that flew through her body when Regulus’ hands moved to rest over her cheeks. 

She knew that neither brother particularly liked the other. She knew that there was some weird, unspoken, competition going on between them at all times. And she knew it was wrong to use Regulus to get into Sirius’ head like he had been getting in hers for as long as she could remember. 

But then Regulus moved one of his hands down to her exposed leg and gave the soft skin a small squeeze. His fingertips were inching upwards and when they rested at the hem of her short skirt he pulled away. 

“Should we go into my room?” She nodded her head and did her best to keep up with his long strides. 

On the way up there she noticed it was a quarter past three, she had done the hard work of her plan, but there was still one more thing she needed to do to ensure her plan went smoothly. 

As soon as they were in Regulus’ bedroom, she shut the door behind them and brought her lips to his again, bringing her hands into his hair and tugging slightly at his loose curls. 

She kissed him with all the fervour she could manage and it paid off because Regulus' hands instantly went to her hips as he took a step back in hopes of finding his bed. 

Perfect.

When the backs of Regulus’ thighs found his bed he sat down and she followed, putting her legs over his so she was straddling him. 

When she pulled away from kissing him to get comfortable, Regulus could see from his peripheral vision that her skirt had ridden considerably high and he was sure he could see a bit of black lace poking out. 

Immediately she went back to kissing him, this time, letting her hands rest at the hem of his shirt, her fingers toying with the thin fabric. 

She didn’t think it was fair to compare how the Black brother’s kissed. Sirius was always fierce and passionate whereas Regulus was a little more gentle with his passion. She reminded herself that she was exactly in the position she needed to be and she didn’t need to force anything, so she let herself copy Regulus’ passion and slowly let herself relax. 

Regulus' hands were resting where the backs of her thighs met her bum and her skirt, doing little to cover her, rested on the back of his hands. 

It was here that Regulus realised he had been lying to himself ever since that first night when he saw her in the kitchen. The weird feeling he kept pushing away was jealousy. 

Now, there was a sick part of him that wished his brother knew what he was doing to the one girl he kept coming back to. 

When he let his hands squeeze around her soft flesh, she let her hands reach under his shirt where her fingertips caused a shiver to run down his spine. 

They were still kissing, more messily than they were before. Regulus risked letting his eyes open and he was glad he did when he saw the look on her face. Her face was relaxed with her eyelids closed, long eyelashes touching the tops of her cheeks. 

Regulus was going to savour every moment. 

“I want to touch you.” Regulus said, his chest rapidly rising and falling. She opened her eyes slowly as she pulled back, took her hands away from Regulus' soft skin, and took her top off. Regulus wasn’t surprised when it was revealed she wasn’t wearing anything underneath, her top was very thin. 

“Then touch me.” 

Regulus’ hands instantly found her breasts, he cupped his palms around them before letting his fingers graze over the top of her nipple. She was looking down at him and he watched as her head tilted slightly back and she let out a small moan. 

Sirius had never taken this much care when touching her. 

He continued his movements, watching the way her eyebrows furrowed ever so slightly in pleasure and the way her lips parted as she tried to catch her breath. Suddenly, she started grinding her hips on his thigh and Regulus was sure he was about to short wire. 

“Regulus,” she moaned, when he let the pad of his finger apply more pressure. Her hands went back to playing with the end of his shirt and he barely heard her mutter out an, “Off,” as she tried tugging it upwards. 

Regulus moved his hands away from her breasts and put them back on her hips, moving in one swift motion so she was on her back on top of his made bed, her head resting on his pillow, while he knelt in front of her. 

He brought his shirt over his head and while his vision was covered for a brief second, she took the chance to look at the clock on his wall. Twenty past three. Perfect. 

Regulus’ hands then found the elastic of his pants and started getting them off. Her skirt had flipped up due to Regulus’ movement and now, with his clothes completely off, he wanted hers off too. 

His attention went back to her breasts, but this time he brought his mouth down, letting his tongue swirl around her nipple. 

She moaned, her back arching ever so slightly into his touch as her hands went out to hold onto whatever she could find, which was fortunately, Regulus’ hair. 

Regulus hummed against her skin, pulling back slightly to press soft kisses against her skin as he made his way down her abdomen. 

When he finally got to her skirt, he played with the waistband of it and she watched him think about what to do next. 

He let it snap back down against her skin before he hummed and said, “I think we should leave this on, don’t you?” 

“Well I did wear it for you.” 

Regulus liked that answer. He flipped the fabric completely up, but this time didn’t even wait a second before he was getting rid of the black lace panties she was also wearing. 

“Did you wear these for me too?” He teased, a small smirk forming on his face. 

She squinted her eyes playfully at him. “Of course.” 

“Good,” he said quickly, before lowering himself down to press a soft kiss down onto the skin above her hip bone, before slowly making his way down. 

She wiggled her hips underneath him, whining as he got closer to her core, but refused to go where she needed him. 

“Don’t tease,” she whined, making Regulus chuckle. 

He brought his thumb down to her clit and she moaned at the touch. 

“Regulus,” she moaned, “more.” 

“You’re very impatient.” Regulus tsked, but he let his thumb draw a few more lazy circles before finally letting his finger inside her entrance. 

She clenched around him making them both let out noises of delight. 

He teased her a bit with a few gentle strokes before he added another finger and started to pick up the pace. 

“Fuck, Regulus,” she moaned, her hips arching up to her touch. Using his other hand, Regulus grabbed onto her thigh so it was resting on top of his shoulder. 

And Regulus was certain this was a much better angle because all of a sudden her eyes widened and she was struggling to form the word that was on her lips. 

“Is that good, darling?” Regulus teased, not confident in her ability to answer him. 

She nodded, small noises escaping her lips as Regulus continued to reach the spot that Sirius usually avoided. 

It was hard to think with the way Regulus’ fingers were moving inside of her. He kept a steady pace and he had moved his other hand down onto her hip to stop her from wriggling. But she still managed to sneak a glance at the clock.

It was finally three thirty. 

“Regulus,” she moaned out, her voice a bit more breathy than she would have liked. “I want you in me.” Her voice went up at the end of her request and Regulus let out a low chuckle as he got in a few more strokes before he pulled his hand out. 

She kept her leg resting on his shoulder and she knew that she was close to release, but she hoped Regulus was too. 

He was hard and she couldn’t help but stare as he leant over to reach for the square packet in his drawer and fumble to get it open. Thankfully, it didn’t take long for him to position himself at her entrance. 

She was getting impatient. 

“Don’t tease,” she whined, her voice a little more shrill than she would have liked. 

“Merline,” he grunted, finally giving her what she wanted, “you’re bossy.”

But she didn’t care, she let out a loud moan, louder than what she had been this whole time, but Regulus found his pace and he didn’t seem to mind. 

She brought her hand down to rub at her clit. She knew it was messy and rushed, but it was already past three thirty now and she needed to hurry up. 

But Regulus already knew where the spot that brought stars to her eyes was and she was glad that Regulus understood the urgency of the situation because he was not holding back. 

“Fuck,” she screamed, “Regulus.” She thought she should be paid for the noises she was making. There was a brief flash of embarrassment that crossed her mind at how lewd she was being, but she had come this far and she wasn’t backing down now. 

“Fuck, fuck fuck,” she chanted when Regulus fingers found her nipples, giving them the same attention he had done previously. “Regulus!” She screamed, when the tight knot that had been tied in her tummy quickly started to unwrap. 

Regulus’ hips were moving faster and she didn’t really have to force the scream that left her throat as her body tightened in pleasure. Her hands went out to grip the sheets and she was slightly aware of Regulus slowing down and grunting out her name before removing himself from her. 

Over their heavy breathing she could hear footsteps outside and had to stop herself from smiling. She had done it. 

The weight of what they had done seemed to settle over them as Regulus laid down beside her in silence. It was heavy, but she didn’t mind. It was heavy, but Regulus thought he would have been able to carry it. 

When their breathing slowed down she turned to Regulus. 

“Thank you, that really helped.” She leant over to press a kiss to his cheek and then stood up and got dressed. 

Regulus laid there in silence. 

He could hear her feet scuffling around as she organised herself quickly and he heard her say thanks again before his door opened and closed and Regulus was reminded why he wasn’t in to hookup culture. 

As she walked through the corridor she saw a familiar figure leaning against his bedroom door. 

They stood in front of the other, Sirius, with his arms folded over his chest and a scowl etched on his face, and her, a sheepish grin ghosting her lips. 

“I told you you’d put out for anyone with a pulse, how dare you bring my brother into this.” 

She shrugged her shoulders innocently. 

“He was the one who offered.” She sent him an innocent smile before making her way down the stairs. She could feel her heart in her throat and she hoped she’d be able to make it down without falling.