A/N: Another slow chapter, though I hope it's still enjoyable. I just couldn't resist the flashback-tbh I just want to see them happy.

In the Grimmauld Place dining room, now fully composed and collected, Klara was setting out sandwiches she'd bought on her way home when someone spoke from behind her.

"You're back."

It was Sirius.

Her breath caught. God damn it, his voice. The rich sound expanded in her chest, warm and comforting and exciting, with that familiar touch of roughness that made her stomach flutter. She could never help how her body reacted when she heard him speaking. Instinctively, she smiled, before remembering the way things had to be now. She forced the smile from her face, though she could do nothing about the heat that had risen to her cheeks.

Klara looked up, hoping Sirius wouldn't notice her flush. He was leaning against the doorframe to the dining room, looking at her with what could only be described as a stiffly polite smile. Unsettling. He had never looked at her with an expression like that. The strangeness mixed turbulently with the joy and anger already warring at the fresh sight of him.

"As you see," she couldn't help reply. Another strike against the plan to remain politely distant, but really, what else was she supposed to say to such a statement? His lip turned up just a touch, but he turned his eyes to the table, his nose twitching in a most canine manner.

"Is that…?"

"Sandwiches. From Ned's."

His polite smile broke into a genuine one, his cheeks rounding boyishly despite the havoc wreaked by the years. Klara felt her chest tighten.

"Merlin, I'm surprised they're still open," he said, coming to examine the sandwiches wrapped in familiar gingham paper. That first apartment Klara had shared with Pandora Fawley had been five blocks from the sandwich shop, and their entire group of friends had been frequent patrons.

"Are you? They do make excellent sandwiches, so I'm sure business is good. This one's yours."

She handed him the sandwich, taking care that her hands were out of the way of his accidental touch. Sirius sank down into a chair and opened the wrapping expectantly. Klara couldn't help staring at the wiry muscles and tendons that shifted in his forearm as he moved his hands.

"And you remembered my favourite! You're an angel, you know that?" he said, looking at the chicken curry sandwich with the affection due an old friend. "I'd forgotten how much I love Ned's sandwiches."

Yes, Klara imagined as much, especially given how thin he was. Twelve years surrounded by those filthy beings—anyone would forget the things he enjoyed, even if he had managed to spend most of his days as a dog. Her chest tightened again, this time in a horribly sickening way.

"Eat then," she said briskly, choosing to ignore his other comment. "Where's Remus?"

It turned out that Remus had gone to buy Doxycide in preparation for Klara's cleaning plans. In her head Klara couldn't help calling him a variety of colourful names in both English and German. He was supposed to be here, in this house, ensuring that she wasn't alone with Sirius. Twelve hours in he was already shirking on his duties.

Nonetheless, she was an adult, and did not hold these sorts of petty grudges. Klara cast a warming spell over his sandwich and sat down to lunch. It was strange, sitting across the table from Sirius as they ate their sandwiches, yet also comforting, seeing him alive and almost…normal in front of her.

He looked worn, like he carried a constant weight upon his shoulders. There were lines on his face now. The deepest one, Klara noticed with a sharp pang, were between his brows—etched, no doubt, by years of scowling against the demons that plagued him.

Yet despite the leaden pain that surrounded him, she could still glimpse the Sirius she once knew. When he smiled that mischievous smile or raised an eyebrow in that teasing way, when he'd recounted Harry Potter's Quidditch abilities in enthusiastic detail the evening before, he was still so handsome it made her heart ache.

"Klara?"

He had asked her a question, and she realised with mortification that she hadn't taken in a single word.

"I beg your pardon. What was that?"

He gave her a confused look.

"I asked what patients you went to see at St. Mungo's. Uh, if it's okay for me to ask," he added quickly, likely weary from her outburst the previous night. More mortification, as she remembered the exchange and the tsunami tide of her anger. As it turned out, she had grossly overestimated her own self control when it came to dealing with Sirius Black, and Klara had spent the previous night fuming into her pillow over her weakness. Hence the forgotten Cooling Charm.

Now she tried for a smile, her cheeks heating again at the steady way his eyes were fixed on her.

"Yes, you can ask." Then, eager to change the subject, "I went to see the Longbottoms."

Mrs. Longbottom had allowed her to disclose to the Order all she knew, and so Klara gave a wide-eyed Sirius a brief account of the couple's condition.

"So, do you think you can help them?" he finally asked.

"I have to consult my old mentor at the Reinberg, but there are a few techniques I'm thinking might stir some change. I've tried them with past patients, and they've produced results I'd like to see in the Longbottoms." Klara shut her eyes, but she wasn't going to lie to either of them.

"To tell you the truth…the only reason I can help them at all is because of my training in Austria. And because of my specialty work there, and all the unique cases I've treated." She refused to look up at him, but nonetheless felt Sirius go still as the truth of the matter hung in the air between them.

If she had stayed in Britain, she would not have had the necessary training or experience to help the Longbottoms at all. And they both understood, given the choice, she would have stayed until the war ended, and then...of all the cities where she could have studied, Klara would never have gone to Vienna. Not while the ghosts of childhood visits with her Austrian mother hung about the city at every turn.

"And I assume you're…I mean, are you the only one who can do what you do?"

She flashed him a tight smile.

"You're the one who's always said I was brilliant, Sirius. Just because I had a different name and different memories doesn't mean I was a different person. But surely you knew that, when you…"

He returned the humourless smile.

"Yeah. Yeah I did. That's why I chose it."

Klara felt her throat close with the now-familiar anger, but it was laced with frustration, because really, what logic did she have to be angry with him at present? It was looking more and more like all his machinations really had been for the best. What was her indignation when compared to the sanity of two brave, worthy people? She took a shuddering breath.

"Aside from my old mentor, I'm the best Legilimens the International Board of Mind Healers has ever seen. Well, Caroline Müller is. And considering Professor Kowalski is 92 and not so precise with Charms anymore…yes, I am the only one who can do what I do."

"So…"

"So, Sirius. You can stop trying to apologise—"

"For Merlin's sake Klara, but why won't you just let me explain?" Sirius' voice cut sharp and jagged into the silent room, his hand hitting the table in frustration, but Klara didn't even feel herself flinch.

"I don't need to hear you apologise or explain," she said softly. "A fool can guess why you did what you did. You weren't sorry before, and you certainly aren't now." For a second he gaped at her, then he turned away, not contradicting her. He didn't regret it, they both knew.

"I am sorry that you're angry, Klara," he finally said, uncommonly quiet. "And I'm sorry that you'll never trust me again."

She frowned up at him. Was that what he thought? Instinctively she reached for his hand, the way she'd always done when reassuring.

A mistake.

Skin on skin, so very hot, and they both jerked back as if burned. Klara pursed her lips, her heart suddenly racing, and tucked her hands under her legs to keep from reaching out again. There must be none of that. Not anymore.

"Why would you say that?" she began instead, surprised she could keep her voice light. "Sirius, I trust you with my life." His head snapped up, eyes bright, lips parted in surprise. She felt her frown deepen. "That never changed." How could he think she would ever doubt him? Hadn't she said she understood his reasons?

His breath had quickened, and she could see the outline of his chest rising and falling against his thin shirt. His eyes, dark and dense and wild now, fixed into hers so intently as to almost cause pain. She did not want to look away.

Unhelpfully, foolishly, Klara wanted to reach for him again, damn logic and good sense. Her fingertips still throbbed from the brief contact with his hand, and her skin screamed for more. Instead, she ripped her gaze from his, fixing on a spot on the carpet. If she could not control her mind, at least she could control her body.

Sirius said nothing. He had something to ask her, she could tell—could feel the question burning just on the tip of his tongue—but it never came.

After what seemed like hours, Klara heard Sirius slump back into his chair. Composed once more and daring to look back at him, Klara saw with a leaden ache that the light from before had died out of his eyes. No. Better like this, she chided herself, gritting her teeth. Better that they both understood how things had to be. And she rose from the chair and left the dining room before her fragile resolve could weaken any further.

O~O~O~O~O

"Are you going to tell me what you're really up to with all these extra Defence lessons?" Sirius asked. It was end of October, Seventh Year, and they had made a routine of sneaking up to the Astronomy Tower on nights James Potter had patrol. Klara rested her head in his lap as he leaned against the battlements, the crisp autumn air refreshing against her flushed skin. Sirius lazily wound a curl of her hair around his finger. His other hand traced up and down her naked arm. It tickled deliciously.

"As I've told you, I simply need the extra help," she said innocently, though she knew he didn't believe a word. He knew her well enough by now, and she could tell him this. Wanted to tell him, to share this secret.

"You might be a natural liar, love, but it's pretty obvious DADA is not where you need extra help."

She swatted half-heartedly at his hand, and felt more than saw his smirking grin in response.

"Prat. Didn't you lure me up here with promises of Transfiguration help? I must say, you're not much of a teacher."

"I'm a great teacher, actually. You're just a naughty student."

"Oh!" He'd pinched her bum. She caught his hand, face flushing. "Sirius Black!"

He raised a challenging brow.

"What?" It was his turn to play innocent. She widened her eyes in what she hoped was a menacing way, then turned them to the hand still in her captivity.

Slowly, she let her thumb massage up his palm, running her fingers along the hard tendons and flexing muscles, soaking in the warmth of his skin. She could still feel the imprints of his fingers on her back, where he had gripped her waist.

She looked up at him, eyes locking right into his, and sucked two of his fingers into her mouth.

His grunt of surprise was raw, and she let her own satisfaction gleam in her eyes. She lapped her tongue over the light callouses on his fingertips, eliciting longer, hoarser sounds. His skin was salty from their earlier exertions, and she let herself savour the tang of him for a moment before she bit down on his knuckles—just hard enough to sting.

Another grunt of surprise, and when he looked down at her again there was a dangerous glint that wasn't there before. Klara felt her belly tighten. She managed to give him a lazy half-smile, but was too aware of his body stirring again under her shoulder, too aware of her own body's flickering heat in response.

He reached to lift her to straddle him, and it was with great difficulty that she stayed unhelpfully limp against his arm.

"I thought you wanted to know why I've been taking extra DADA lessons," she said, trying to keep the breathlessness out of her voice. Sirius growled, but stilled, and for a few heartbeats she could feel his body warring with his curiosity. Eventually, curiosity won.

"Don't think you're off the hook." He said darkly. "Let's hear it then."

"Professor Lam has been helping me practise Legilimency."

He raised an eyebrow.

"You mean to say you can't read minds already?" Ah, so he had noticed how transparent he and his friends always were.

"One doesn't need to be a Legilimens to read a Gryffindor's mind," she said airly. "But in all seriousness, you know perfectly well I'm not a natural Legilimens."

"And why's she teaching you specifically?" he frowned. All the Gryffindors seemed to think Professor Lam was somehow involved in the Dark Arts, even though, in Klara's opinion, she was the best DADA professor they'd ever had.

"I asked her and she was happy to help," she shrugged. "I found a couple books in the Restricted Section in September, and—" she bit her lip, trying to contain her excitement just talking about the subject.

"Oh, Sirius, it's the most fascinating magic. I tried out some of the theory on Pandora and Louise, and actually managed to get into Louise's thoughts a few times, but the books both ended by saying I needed to find a real live teacher. So. I thought I'd ask Lam, and low and behold. Extra lessons."

His eyes widened, then narrowed.

"Hmm. Klara, is this even legal?"

"Um, I don't think so, but when have you ever cared about legalities?" He shot her a conceding grin.

"Never, naturally." A low chuckle. "So don't worry. I'll keep your secret."

"I should hope so. I'll know if you intend not to, and you might find yourself in an undesirable condition."

"Oh?" Sirius gave her a taunting look. "But joke's on you, love. My family taught me loads of rubbish, but they did manage to teach me Occulmency too."

"Ah, I see," said Klara, settling into his lap and stretching out luxuriously. "You think you can shut me out, do you? Unfortunately, the books are very detailed about how to work around Occulmency. We'll see how long you hold out when I try it on you."

Sirius was looking down at her very intently now, the slow, awed smile spreading across his face stirring a sweet flutter in her stomach.

"You really are brilliant, aren't you?"

"I mean, I am, but I'd still like to hear why you think so."

He laughed. "Growing up, my uncle Cygnus tried to teach Legilimency to every one of us cousins. He was prouder of his Legilimency than he was of his three daughters combined, I imagine, and he was very disappointed none of us could pick it up." Sirius' eyes gleamed, and he shook his head, looking a little rueful.

"And here you are, learning even the hard stuff from a book. Brilliant."

"Well," mused Klara, trying to hide her glow at his praise. "Everything worth learning can be learned from a book somewhere."

"Right. Well, you're wrong, but I'm not going to start an argument about books with a Ravenclaw."

Klara only smiled and shrugged. She'd had enough talking. Every breath Sirius took pressed the hard lines of his body into hers, and it was becoming difficult to breathe.

She propped herself up against his chest, letting her hand accidentally brush along his firm stomach and drop into his lap between them. A sharp intake of breath, and she felt the tightness in her belly stir again, moving into liquid heat between her legs.

"Now then," she murmured, tracing the shadows moving in his throat as he swallowed. His skin was so soft there, so fine, like velvet under her fingers. "I remember you saying you weren't letting me off the hook."

"I haven't forgotten," he said into her ear. It tickled, hot and low, and Klara squirmed. "I still need to get you back for biting me."

"Cheek. I only bit you because you pinched me."

"Payback for this, you mean?' He did it again, and she felt heat flood her face.

"Sirius!"

"Tsk tsk, love, keep your voice down. We haven't even gotten started."

O~O~O~O~O

Sirius knew better than most the extent of Klara's talent at Charms. He'd also seen enough of her post-Hogwarts apartment to know just much time and energy she was willing to expend for a pristine home. However, he could not help harbouring great doubt that she could clear the mysterious sticking fungus from the kitchens.

He and Remus had made another valiant attempt that morning, even locating a tattered cleaning guide in the library. Again, they could boast of barely a foot of progress, though they had only been disturbed once by Kingsley passing through. When Sirius relayed this position as they waited for Remus to finish his lunch, Klara only raised a dark brow at him.

"I'm going to find a way or die trying."

Now, as Klara muttered her eighth spell at the same area of slimy green, Sirius was beginning to worry that they were all going to die trying to wage war against this demonic growth. According to Klara, it was called a name that sounded like "mumbling," and supposedly came from the Red Sea region. Sirius wouldn't have been surprised if Kreacher had taken some fungus from between his toes and multiplied it to cover the kitchens.

Kreacher had slinked upstairs after making the biscuits the previous day, and Sirius hadn't needed to call him, thank the Gods. Now, though, he wondered if he should summon him and try eliciting his help with the mould again, even if the elf had been adamant that he didn't know how to get rid of it.

Then again, Klara had yet to lay eyes on the fiend. Perhaps Sirius should let her keep her peaceful existence for as long as he could. When they moved to the upstairs rooms Kreacher would inevitably rear his wrinkly head. Just thinking about the things he'd have to say about muggle-born Klara…Sirius cringed.

A hum of triumph cut through Klara's murmurings. Sirius turned sharply to where she stood. She was grinning a rare wide grin at the two of them, a patch of char at her feet. Her mass of curly hair was braided around her head and held back with a red scarf. In that moment she looked so young and radiant Sirius felt his chest warm just looking at her.

"I've got it," she announced unnecessarily, and pointed her wand to another cluster of green. "Torreo."

An orange spell one normally used to toast bread shot from her wand. In an instant, the patch of green began to brown and shrivel, but Klara kept her wand steady, casting the spell longer much than Sirius had ever seen it used. After some moments, the new patch had turned the same blackened colour.

"Have you literally just…incinerated it…?" came the mild voice that Remus usually slipped into when overwhelmed. Sirius looked over to see him blinking at Klara with a mix of confusion and alarm.

Klara smiled her quiet smile at him.

"Burnt to a crisp, as they say, but the charm should be gentle enough for the furniture. And now—" she cast a regular Siphoning Charm, sucking away charred dust and revealing the red tiled floor. Sirius and Remus stared at the clean spot that would have taken the two of them a couple hours at least, their jaws slack.

"Right then, if you'd like, I can roast while the two of you siphon," she said, already approaching the next area of green with a dangerous gleam in her eye. Remus turned, giving Sirius a meaningful raise of the eyebrows, as if to ask how this woman, who seemed so eager to incinerate things with a toasting charm, hadn't yet burned Sirius to a crisp. Sirius just shrugged, avoiding Remus' gaze.

He had never understood Klara completely, and she was even more of a puzzle now—her temper unpredictable, her anger obviously still raging, but sometimes Sirius would catch glimpses of other emotions he didn't have the chance to place.

Yet the worst thing about the current state of affairs was that her deliberate politeness made it clear she had no intention of continuing whatever it was that once existed between them, and Sirius, despite claiming this was the outcome he'd expected, thought maybe he'd prefer it if she did want to burn him to a crisp.

What a greedy bastard he was. Just yesterday he'd been telling himself he was satisfied so long as she spoke to him, and already now he wanted more. He wanted her to smile at him, really smile, or grip his hand in that warm way she always did, though maybe it was smart that they didn't touch, given the little shock at lunch. His hand still buzzed.

It took the three of them an hour to char and siphon away the green fungus. Afterwards, a buoyant Klara cast a series of spells gleaned from her doorstop of a German housekeeping book while Remus made tea on the magically scrubbed stove.

The long table and chairs seemed sturdier, the wood smoother, and the metal surfaces of the hardware gleamed as if new. He and Remus packed up the old pots, pans and chipped dishes into rubbish sacks, while Klara unpacked cookware and utensils from her clipper bag, arranging them alongside the china sets she deemed still usable. (She had agreed that some of the plates Sirius had isolated were rather nice.)

Klara organised her groceries with a final flick of her wand, then sat back with the tea Remus handed her, eyes crinkling. Looking around to survey to work they'd done, the kitchen suddenly seemed warm and bright and pleasant. Sirius was certain he'd never seen it so welcoming in his life. His mood lifting like a balloon full of hot air, Sirius looked over at Klara's giant book and couldn't help himself.

"You know, that was very Ravenclaw of you," he said, pointing to the book with his chin. "But it probably would have served more purpose if you'd brought it out before you tried fifteen scrubbing charms." He heard Remus choke slightly on his tea, but Sirius always felt as if one was not truly living if one did not constantly try to provoke irritation from Klara Montagu.

Klara only gave him a sideways look and drained her teacup.

"Certainly not," she said in that dignified voice that always reminded Sirius of McGonagall, (though he liked to keep his tongue and so had never told her this outright.) "This is only a housekeeping book, not a field guide to Middle Eastern seaweed." More coughs from Remus. "Now then, if you gentlemen are done with your tea break?"

O~O~O~O~O

They proceeded upstairs, Klara taking on the distinct air of a wartime general as they shuffled into the dining room.

She taught Sirius and Remus versions of dusting, scrubbing and restoration spells that she'd modified to cover large areas at once-clever, brilliant woman. They set to work once more. Though it seemed Klara was far more efficient than he and Remus put together, soon the rugs were plump, the draperies plush, and the floorboards free from cracks and holes.

At Klara's behest, (and after some teasing about her abysmal Transfiguration abilities), Sirius conjured a wrought iron cage, and she and Remus took turns targeting the Shropshire Pixies with Freezing Charms while Sirius caught them and popped them inside.

There were monster mutant spiders that none of them had been prepared for, lurking in the cabinet housing the official Black family china. After Remus hastily immobilised them, Klara, who had scrambled to sit atop the dining table, afforded them the same treatment she had given to the kitchen fungus, her face stiff with distaste.

Soon, the room looked as if someone had exploded a time turner inside and blasted it twenty years into the past, but Sirius could feel his good humour deflating by the minute. He looked around nervously now, suddenly engulfed by the dark wood and Slytherin green fabric dotted with silver serpent detailing. His extended family sneered down at him from the fireplace, Bellatrix and Uncle Cygnus seeming to glare most sharply, and Sirius shuddered, trying not to remember the family dinners that has dragged and gnawed. Unlike the kitchens, this room in its original state bore the distinct characteristics of the Black family to its bone, and Sirius hated it.

Restless disgust bubbled in his chest, not helped by the buzzing of the pixies that had crept up again as Klara's Silencing Charm wore off. Turning his head as he siphoned off the last traces of dust from the mantelpiece, he found Klara studying him with an unreadable consideration. He raised an eyebrow, and she turned to survey the room.

"Sirius, would you mind terribly if I did some redecorating?" She walked around the table, casting another offhanded Silencing Charm at the Pixi cage. Blissful silence.

"Mind? Be my guest. I'm starting to wish we hadn't cleaned the room at all now. It's much worse when everything looks the way it did when my whole family was around."

"We can start with those photographs then," she said, pointing at the photos of his parents and cousins, and after a pause of consideration, Sirius grinned. He'd gotten so used to seeing them that he'd forgotten they weren't stuck to the walls like her mother's portrait. Klara smiled and popped out the photos, tossing them into the rubbish bag with the china. Though he was sure he imagined it, Sirius thought the dining room felt just a touch less oppressive.