The first half of this is the lead up scene from Sirius' POV, but if you just want to read the lemon it's clearly marked if you want to scroll about halfway down and start there.

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Lupin came up and grabbed the back of his shirt though, hauling him just slightly around Frank like a scolded puppy, and adding to the effect by saying, "come on Padfoot, bath time."

Only the very real threat of hitting Remus if he moved to hex Longbottom allowed himself to be dragged off like a scolded child, the ingrate. He did not acknowledge James either, the betrayal still radiating off of him no matter his brother trying to talk to him as he walked past, and he forced himself by the barest hint not to slam into Peter either when he spoke up next instead, he just did not want to touch anyone right now or he'd hurt someone that wasn't that bigot.

Instead he dropped trow in record speed and went to the last stall to slam the door behind him and turn the water on, as hot and high as it would go so he didn't have to hear what Remus and James were suddenly whispering about and pressed his face against the temporarily still cool tiles as he bit his lip to stop himself screaming in frustration.

Just one bottle cracked over his head in retaliation, was that so unreasonable to ask for? He'd have encouraged Remus to heal the cuts himself just to make that arsehole see Moony as an f'ing person! What the hell did James mean by it, stopping him when he'd thrown curses in the corridors for far lesser slights on any of them!

The anger had been so all consuming he'd thought up a dozen spells in record time to use but still wanted revenge more than anything, he'd have thrown that arsehole to the floor and done the deed, then stepped aside to clean up he was sure...so long as Remus was okay and he clearly was...

His head was pounding so hard he wouldn't be surprised if blood was trailing out of his own ears. He was lying to himself and he knew it, once he'd started there was a very dangerous edge still serrating his insides that promised he may not have stopped before something irreversible happened. James would have stopped him before it went that far though, he could have at least gotten a few good licks in-

"Would hitting him have really made you feel better?" Remus' voice startled the response from him.

"Yes!" Merlin, anything to get this pent up feeling out, he'd be shagging Remus senseless right now if he could stand to look at him either. Moony had grabbed his hand, tried to tell him to calm down, and he only hadn't followed the others into the showers and played along long enough to swear a bit more and ignore him. This was infuriating, what had he done wrong this time that both of them so suddenly whole heartedly disapproved of!

"Really?" He could hear the strain in Remus' voice to keep himself calm. "Think about the last two times you did something without thinking first Sirius, has that actually made anything better?"

He pulled his face off the wall and looked back at the closed door. The look on Remus' face when he heard what he'd done to Snape, the look on Peter's face under the Dark Mark...so maybe he'd over reacted a bit in those instances, but he still felt justified in this one! They were two very different things! He opened his mouth to say something, but his chest hurt so damn bad and he was too confused as their faces swirled around like a top. He didn't know what was going to come out and quickly closed his mouth back and pressed his forehead against the wall instead again. It wasn't remotely cool anymore, and the hot water was starting to make him feel dizzy.

"Look, I'm not happy with Longbottom either," he continued and Sirius wished he wouldn't so much he bit his lip again, the pain the only thing stopping him going out there and hitting Remus next to make everything stop. Merlin, what was wrong with him? "Merlin knows I'd love it if nobody ever assumed I was some bloodthirsty animal again, but Sirius did you ever think, maybe he actually doesn't know better?"

"That's ridiculous-" they'd spent days forced into each others company now and Remus hadn't done a damn thing to anyone! Moony's actions were not on Remus, any sane person should know that, and neither him or the girls had been hurt!

"Sirius, you know better than anyone what others think of me, but you three actually got to know me before you found out."

He went colder than ever, actually shivered and swayed on the spot for the vertigo that erupted in him. Oh yes, his heritage had made it very clear what Remus was and wasn't supposed to be like, and his parents had been so insanely wrong it would have been funny if it didn't make him despise their existence now, teaching him so many things about someone who was now one of his very best friends.

Longbottom hadn't bothered to take the time to get to know Remus at all, he was no better than Regulus, just believing whatever the hell he was told. "Wouldn't kill the guy to ask then, rather than treating you like that!"

"Have we really given him the chance?" Remus asked mildly. "I know I haven't exactly stepped up and offered to be their guinea pig if they have questions, I doubt you lot have." He paused for just a moment and his stomach was clenching so hard he wondered if he was going to throw up, and if the tiny little drain at his feet would manage it without him getting out. "Maybe Peter's been saying something to Regulus, but I kind of doubt it." So did Sirius. He had zero clue what those two were talking about now, but it couldn't be that, his idiotic little brother had a sycophantic need to please their parents and probably would have cursed Peter if he'd tried to say otherwise.

What the hell would he do when that inevitably happened, those two were nothing alike and if they did try to kill each other would he even step in? His vision started swimming, he was now leaning against the wall for support for the actual need of it as his breathing increased. He'd never asked himself in his life if he would intervene in a fight, it came naturally to him, but damn it all if Remus wasn't right. If those two went after each other, he didn't know who he'd back up because both were on his shit list for various reasons, if he thought about either too long this awful feeling crawled up his throat and he had to quickly change topics lest he do something else.

James had promised they still had time to work on it, but he didn't know how to do that!

All Remus was asking was that he think about it before he hit Longbottom. Not that he couldn't despise the blonde git in the meantime, and Moony was very right that his actions had consequences he couldn't ignore forever. Merlin did he just want his head to stop hurting, so he finally agreed with whatever sanity he had left to do it Remus' way, his clearly wasn't working even for him. He didn't care if Frank Longbottom hated him, but he wouldn't go back to Remus hating him, he couldn't bare it. "Alright Moony. He, well, you're the one wronged here. If you really think a lecture is the punishment he deserves, well, I'll back you up on that. It's probably worse than what I could do to him anyways."

LEMON~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There was a beat of silence. Sirius tipped his head wearily back towards the door, wondering if Remus had left and what the hell he was supposed to do to make up for this, no amount of blue jabs in the world was fixing this mess-

The door opened, and Remus slipped inside, closing it firmly behind him. Sirius straitened up in surprise to see him only in his boxers, somehow the conversation before seemed a hell of a lot funnier now that he knew that, but Moony didn't seem in a chatty mood anymore, or maybe he'd just finally done the right thing for once. It certainly felt that way when Remus grabbed his waist and pressed a kiss down hard on his neck that he felt through every drop of water and every thick strand of hair in the way.

A shamelessly relieved moan escaped him as he bucked on instinct, fingers now digging into the wall in front of him for quite another reason as Remus released one hand to start pushing his hair aside and continue while full on riding him from behind.

"Fuck," he panted more in shock than anything, but the laugh that escaped him had never felt so good as he let one hand off the wall to clench tight on those driving hips, pulling hatefully on the material still in the way. "Careful there Moony, or I'll never disagree with you again."

"I'm still in shock you listened, let alone that worked," he breathed into his ear, his lips still stopping to kiss behind the cartilage and everywhere else he could reach. "Merlin Sirius you really are starting to grow up."

"I should be offended," he grunted as he still couldn't get the blasted boxers off and Remus was not helping as he kept his pace, "but dam it Remus I really, really f'ing needed this."

"Then I'm happy to oblige," he promised, though Sirius cussed again when he took a step back. He couldn't even turn fully around though before Remus had him pinned back to the wall, the slick water had nothing on where every point of contact felt alive. Remus busied himself for only a moment with the soap and Sirius shifted restlessly, even reaching up to grab the shower head impatiently and trying to turn around, but Remus reached one hand up to keep it there and the other fell back to his waist to hold him as he gently began easing himself up.

Sirius was in no mood for that and pushed back hard, swearing for all his worth as finally he could feel that bliss again of being full and alive as his every nerve jolted with pleasure.

Remus' hand released his from the shower head and slapped down over his mouth while hissing still near his ear, "keep it down you idiot."

He shook his head in protest and moved again, frustrated the little tease had stopped now and grinned when Remus finally released a huff of pleasure himself, his hand slipping a bit to hold his neck instead. "Now who's pillow talk is lacking?" He shot back, only just keeping his voice at some standard of normal. It's not like he wanted the others to come back.

Remus didn't answer, keeping one hand lightly under his jaw and keeping his head tilted back just enough it was a pretty good reminder, the other on his waist as he finally picked up that glorious speed again and Sirius only just kept himself in check from panting and thanking him to his hearts content by the light fingers dug up under his sensitive throat.

The feeling of flying higher than the stars mounted with each jab, it hurt just the perfect way as his body built up the best release and nobody had ever tried to do this to keep him quiet before, so when his toes curled and he finally burst a stream of semen he couldn't help but moan Remus' name with nothing short of reverence and relief.

Moony still took a couple of strokes to come, every one of them tugging something in him that was like prodding the spent bundle of nerves to see if anything else could possibly come out and it always worked as he kept gasping and spasming as finally Remus came inside him, both hands tightening almost frighteningly down and he chocked in surprise and tried to pull away now.

"Sorry," he gasped, not sounding very sorry at all as his hand dropped down to hold his waste with both hands now and just breathing in the still warm water and resting his forehead against his shoulder.

Sirius finally let his arm drop, it felt numb from being suspended like that so long and he flexed his fingers for quite a few moments to get feeling back in them from how hard he'd clenched at the metal. "Well don't apologize to me," he said sincerely enough for both of them as he tried to peek over his shoulder at him. "We both knew you'd finally act on those threats to strangle me one of these days, and this is how I'd be okay going out."

Remus giggled for a moment and pressed a kiss to his shoulder blade before finally easing off of him. He felt oddly hollow afterwards and fought off the urge to tell him to go back for seconds already. He turned and they watched each other under the streaming water for a few moments before Remus reached up and began stroking at his tangled up hair, speaking to the long locks quietly, "I didn't think it would go this far this fast."

Sirius shrugged and didn't seem particularly bothered by it, but then, nothing ever seemed to bother Sirius for long. "All in good fun Moony, right?"

Remus bit his lip to stop himself blurting out that no, it wasn't. He'd crossed a line he shouldn't have without saying something to Sirius about this, he'd really been planning on being honest before he allowed this part, but it was too late to go back now. He was still playing with his hair rather than answering and Sirius clucked his tongue impatiently and turned back to seize the shampoo like nothing had even happened, beginning to go through his routine and even starting to hum after a few moments.

He just leaned against the stall and watched in fascination something he'd never let his mind imagine, lest he have to run off to a bathroom that wasn't occupied. Sirius didn't seem to mind, of course not, when did he ever care about having all attention on him, even doing this?

When both of them felt clean enough Sirius turned the water off and opened the door while Remus gave his sopping boxers a disgruntled nudge before picking them up and hanging them on the door to dry. He was definitely going to regret later not knowing the charm to instantly dry them, but it was the best he could do.

Sirius was already half dressed by then, combing his fingers impatiently through his hair and fidgeting with his fly before deciding to take drastic actions. Fixing his pants and throwing his shirt on, he hopped onto one of the sinks and tapped one of the handles. It fell off with an annoying little clatter that had Remus still checking the door uncomfortably and unwilling to leave the stall as Sirius transfigured it into a gleaming comb and brushed his hair out with a content sigh.

"Glad you got that out of your system," Remus told him with genuine amusement. "You legitimately looked likely to kill Longbottom before."

"Don't be so dramatic Remus, that's my title," he sniffed. "Are you coming out of there or not?"

"Um," he muttered, somehow still embarrassed despite what they'd just done to go into full light in front of Sirius, let alone admit his problem.

Sirius snickered though and seemed to guess anyways, hoping down when he was done and giving Remus a gentle push back the rest of the way inside before tapping his dripping cloth. It dried, mostly, and he snatched them on with a grumbled thanks.

Sirius watched him get dressed now with a look of curiosity, and he tried not to flush red as the scarlet robes when he fixed his shirt and walked past for the step down. Sirius caught his elbow though and gave him almost a shy grin. He tugged on his arm and looked at the open wall with a questioning look, and Remus was too curious not to follow no matter how tired he was starting to feel.

Sirius sat down and Remus followed suite, just watching Padfoot build up whatever it was. He wasn't quite expecting, "thank you, really, I'm kind of, well I've never admitted to you guys, but it really does feel-"

"Oh, hey," Remus gripped his arm tight. "Don't apologize, I was teasing you."

"Right," he still looked a little on edge. "Some of the other guys though, they think its funnier than sin even while they're doing it to me, and I just, damn Remus if I would have known you could just shut up and shag me I'd have traded you in a heartbeat."

He didn't even get a fleeting chance to enjoy those words as a white hot flair of possessiveness spiked so hard in him his grip went bruising for a moment and Sirius looked at him in concern. "Relax Remus, nobody's taken advantage of me, just shittier pillow talk than yours."

"I, um," he pulled his hand back carefully and still studied him in concern despite Sirius' sincere tone. "Sorry."

"We are so done with apologies for the day," he scoffed and waved off.

"I'm curious though-" he couldn't stop himself saying.

"Want a list of names?" Sirius' grin turned teasing.

He rolled his eyes without comment. "More, just curious, I mean you know who I've been with but-" no he was not thinking about hunting down and castrating anybody, not at all...

Sirius shrugged and leaned against him on the wall now, looking at the ceiling as he answered like that would hide his tone was still a bit on edge rather than as cavalier as he was clearly still going for. No matter what he told himself, Remus could tell Sirius was still a little on edge about something. "Well, Eros got me onto the idea, but that was accidental so I-"

"Professor Eros?" He yelped in disgust, grabbing Sirius' arm without even consciously thinking it this time. "Our current DADA teacher?"

"Relax Remus, please, he's got an age thing, bloody wanker," he huffed. "Walked in on him and Benjy Fenwick and it got me curious, so I threatened to tell Dumbledore or give me a shot. Asshole actually said I could go tell, he'd get fired before he slept with someone not of age, can you believe him?"

"I can't believe you didn't- when did this happen?" Remus grudgingly released his arm and put it around him instead, despite the fact Sirius snorted and shoved his chest. Not enough to dislodge him, but enough to make it clear he needed no such comfort.

"Near the beginning of the year, after the detention he gave me for stuffing his desk with dragon dung. Anyways," he said quickly when Remus still looked frustrated, "so I propositioned Benjy instead and he gave me a go, but tried to get me to top since it was my first time with a guy or some shit, and it was still about as good as being with a girl so I convinced him to give me a real go and he did and, ah, yeah. There's been a fair few in the school since then. I'm not ashamed," he snapped at no one, even crossing his arms in defiance of someone, but Remus just tugged so that Sirius was leaning farther into his chest.

He settled and got himself comfortable but still sounded a tad resentful of something. "I feel like I'm screwing this up with you. I'm supposed to be making you feel better, and now you're just pandering me or something."

Remus pulled him tight to his chest and Sirius finally released a long breath. He kept playing with strands of his still wet hair until Padfoot was fully relaxed against him, his head resting over his heart so he could hear the steady rhythm as he murmured, "you have been, more than you know. I said I didn't know how to forgive what you did," Sirius tensed, but Remus kept going in a low, gentle voice, "and I do now. This is helping the both of us, to remember what's important during this awful future, right?"

"Right, yeah," Sirius sighed in relief, his eyes starting to flutter shut. He didn't even seem to realize it, he was still shifting around like he meant to get up but in no way indicated Remus should stop brushing his hair or even pull back.

"It's okay Sirius," Remus promised, putting everything he couldn't say into keeping his voice low and gentle, just wanting to keep this bubble between the two of them as long as he could. Some residual guilt about Prongs starting to feel left out tried to convince him to get up now, but there was just the smallest little jaded thought in him that Sirius had told him something first. James was Sirius' best friend, couldn't he just have this one secret to them?

Padfoot fell asleep only a few moments later. Remus kept telling himself he'd get up in just a moment, he'd take his shirt off and ease it under his head and let him sleep here while he crawled just a few feet away for when the others woke up and came looking. Just a few more seconds...