It starts on a train.

It's on a train that Remus Lupin first meets three boys who will eventually become his best friends and closest confidantes, his pack mates, his family. James and Sirius are already inseparable, despite having just met that morning; Peter has attached themselves to the two, recognising that they might be able to protect him from swaggering fourth-years, and neither James nor Sirius pay him much attention as they natter away about Quidditch and their families and the different Hogwarts houses.

Remus had just been looking for a spare seat. He's always been a small child, even before the bite; amongst the group of students on the platform he'd felt positively tiny. He's aware of the side-eyed glances he's getting due to the scars on his face and arms; he ignores them as best he can until James finally leans forward.

"That's a hell of a scar, mate," he says, gesturing to his cheek, where Remus knows a particularly prominent scar lies on his own. "Couldn't St Mungo's take care of it?"

"Oh, er... I'm half-blood, see, and I was in a car accident with my mum. She panicked, and just took me to the ER—the Muggle hospital," he clarifies at their blank expressions. He feels slightly guilty for the lie, even as he knows he's going to have to get used to uncomfortable questions.

"You've been in a car? A Muggle one? What's it like?" Sirius asks, his eyes wide with wonder. And just like that, Remus has friends.

Sirius kisses him for the first time on a train, at the end of their fifth year. James is off trying to woo Lily, almost certainly without success; Peter is tagging along as he usually is. Despite the June heat, Sirius is pressed up against him, seemingly unconcerned about the complete lack of personal space. Remus' body is humming at the contact, even as he knows it means something completely different to Sirius than it does to him.

At least, he thinks he knows that. Sirius is fidgety, glancing at Remus then quickly looking away, tapping his foot up and down repeatedly. Remus, who is trying to read, finally slams his book down.

"Sirius, what is it?"

"Please don't hate me, Moony." Sirius actually sounds unsure of himself, which is enough to give Remus pause.

"Hate you? Why would I—" the rest of his sentence is lost against Sirius' lips as the other boy presses them against his own. For a moment, Remus forgets how to breathe; it's hot and wet and messy, too much teeth and tongue, and it's utterly, blissfully perfect. That is, until he comes back to reality, pushing Sirius away. He figured one of them would work out his sexuality eventually, probably catch on to his stupid little crush, but he never though Sirius could be this cruel.

"Is this your disgusting idea of a prank, Pads? What, you've figured me out and you thought, sure, let's give him a bit of a snog before I tell him it's never going to happen?"

"What? No, Moony, of course not, I—wait. You... you like me?"

Remus turns away. "Don't play dumb, Sirius. It doesn't become you."

Sirius grabs his arm, whirls him back around. "I'm not, I—I'm gay, Moony. I've fancied you like mad for ages, and I was hoping... but I didn't really think..."

Remus snorts. "You? Gay? Sirius, you've shagged half the female population of Hogwarts—even then, it's only half because the rest are too young for you." Sirius is shaking his head, smiling slightly. "You... haven't? You haven't shagged any of them?"

"Well, a couple of them. Had to be sure, you see. The rest... rumour and speculation."

Remus takes a couple of steps forward, hardly daring to hope. "You're gay... and you want... me?" he asks.

Sirius nods slightly, still looking unsure. Remus takes one more step, until they're pressed nose to nose.

"Well then, Mister Black," he whispers, "show me what I've been missing out on."

Sirius, of course, proceeds to do just that.

He is on a train when he learns of James and Lily's deaths, and who betrayed them. He reads it in the newspaper, of all things, when he's on the way to a job interview in a Muggle bookstore. A wave of nausea overwhelms him as he thinks of the last thing he said to Sirius, and he bends over double. He might keen, or groan, he isn't sure. A middle-aged man steps forward hesitantly, presses a hand to his shoulder.

"You all right there, son?" he asks kindly. Remus straightens up, clears his throat.

"Thank you, yes," he replies, forcing his voice to remain neutral. "I just read some bad news about some friends of mine. In fact, I'd better go get in touch with someone now." He hurries off at the next stop and promptly Apparates back to his apartment, without even checking to see whether any Muggles are watching.

He takes the train to their funeral, too. He sits alone in the back and avoids everyone's eye, unable to face either their sympathy or their suspicion. The remaining members of the Order are there; many of them glance guiltily in his direction before turning away. Remus knows that many of them thought he was the traitor. He knows some of them still do; his relationship with Sirius was an open secret. Only Dumbledore comes to speak to him, and there is nothing in his eyes to suggest he holds Remus remotely culpable for the deaths of two of his best friends. Remus asks after Harry, is told that he has gone to his Muggle relatives, Lily's sister. That's something.

Peter's is the next day. He goes to that, too, but he ends up leaving before it's over. He can't face any more death; can't bear to think about the rest of his life stretching before him, without friends, without Pack.

His final exchange with Sirius keeps coming back to haunt him. Accusations thrown at one another like spellwork; a complete lack of trust between the two of them. So many secrets, so many lies. Even after everything, even with all of his suspicion, Remus had never believed in his heart that Sirius would betray James and Lily. That he could do... that... to Peter. That he would betray him.

He Who Must Not Be Named is gone; all of Wizardkind is partying in the streets, yet Remus is utterly unable to feel joy.

It's on a train where Remus meets Harry Potter for the first time; so like his father to look at, and yet, far more reminiscent of Lily once you get to know him. The Dementors on the Hogwarts Express rattle him, it's obvious, but he won't admit it to anyone. His friends are defensive of him, eyeing him with suspicion when he forces the chocolate into Harry's hands. Remus hopes he realises how lucky he is to have friends like this; he suspects he already does.

He's a remarkable child—teenager, Remus has to keep reminding himself; he's thirteen now, certainly not the baby he had held so many times—fiercely loyal, a gifted wizard, but with a quick temper and something of an attraction for trouble. Remus has to forcibly remind himself more than once that it isn't James he is dealing with, but someone else entirely, and remember to treat him as his own person.

He thinks James and Lily would be proud of their son. In fact, he knows it.

He and Sirius go on a train ride while Dumbledore puts the final wards on Number Twelve, Grimmauld Place; without saying so, they both know it's the last bout of freedom Sirius will have for a while. Things have been awkward over the last few weeks while Sirius has been lying low at Remus'; though they've been in contact ever since Peter escaped and Sirius went back into hiding, they haven't had to dance around each other day and night as they do now. Sirius hasn't made any moves towards him, accepting the threadbare couch with an almost pathetic gratefulness that makes Remus wonder, yet again, just how bad the Azkaban conditions are. There's a tension between them; they are both painfully aware that they aren't the same people they were fourteen years ago, yet they are drawn to each other almost in spite of themselves. Remus has been trying, and failing, to bring the subject up for days.

But on a train ride through the English countryside, Sirius' hand somehow slips into his. He squeezes, just once; Remus squeezes back and grins to himself. They both know without discussing it that neither of them will be letting go again.

All the poignant moments of Remus Lupin's life have been played out on a train; he is therefore wholly unsurprised when the first thing he sees after a jet of green light hits him is a steam engine. He boards before he can think about it too hard; it's almost the Hogwarts Express, but not quite. Far too clean, far too modern. He wanders through, passing compartment after compartment as he feels the train begin to move beneath his feet. He wonders, idly, where it is taking him.

There is a dark-haired man with glasses standing at the end of one corridor; for a moment Remus thinks it's Harry, and he feels sick. It takes a moment, and the appearance of a familiar, yet almost forgotten red-headed woman before he realizes the young man isn't Harry, but his father; it suddenly strikes Remus in a way it never had before just how young James and Lily were when they died. None of them felt young at the time; the horrors of war seeming to age them years in the space of weeks. He knew it clinically, of course; knew that they were just a few years out of Hogwarts, that they were both only twenty-one. And yet, knowing isn't the same as seeinghow little difference there is, age-wise, between Harry and James. He aches for them, then; all their missed years, all the stolen moments with their son.

James grabs him then, pulling him in for a rough hug. "It's good to see you, Moony," he mutters against his shoulder, his voice rough. Remus wonders how time has passed, for them; if it has at all. Has it been seventeen years for James? A heartbeat? A lifetime?

He hears a thump, feels James flinch against him. He looks up and realises Lily has smacked her husband over the back of the head.

"It's good to see you, Moony? Really? He just died, James. Joy isn't really the appropriate reaction here." She's smiling at Remus when she turns to him, though her eyes are bright and watery, and she wraps her arms around him. "Is there anything you need, Remus? Anything you want to know?"

And really, there's just one question; the obvious question. He's not sure how to articulate it; thankfully, time doesn't seem to have diminished how well they all know each other.

"He's in there," James grins, jerking his thumb towards the compartment behind them. "We figured you'd probably want to see him on his own; I'm surprised he's lasted this long without bursting out of there and grabbing you, actually."

"I thought he should come on his own," Lily interjects, "but my dear husband insisted you have a 'proper welcoming party'. Tactless, this one."

"We'll leave you two to have a proper reunion, then," James says. He's trying valiantly, but can't wipe the smirk off his face. "We'll see you when we get there, Moony!"

Remus barely hears him; too busy staring at the door in front of him. His hands are shaking as he slides the compartment door open. Before he can even blink, there are two oh-so-familiar hands on him, pulling him close.

"Moony," Sirius whispers against his lips. "Moony, I missed you so—"

"Shut up, Pads," Remus mutters. It's been two years, after all; two years without the smell, the touch, the tasteof Sirius. He pulls the other man close, kissing him soundly, and together they lose themselves.

"Do you realise we kissed for the first time on a train?" Remus asked later, when they're both sated, and immediately wants to bang his head against the nearest solid surface for sounding like such a girl. Sirius just chuckles, though; Remus can feel the vibrations underneath his ear where it's resting against Sirius' chest.

"How could I forget that, Moony? Bloody terrified Prongs was going to come back and spring us; wasn't really the way I'd planned on coming out to my best mate."

"I'm not sure the way he found out was any better."

Sirius grins as he remembers the look on James' face when he came back early from Quidditch practice to find the two of them in a verycompromising position on Remus' bed. "Poor old Prongs. I think he was appalled that he hadn't noticed, more than anything."

Remus nods quietly. It's all starting to catch up to him now; the battle, Fred, seeing Tonks go down just before he did. Teddy. Sirius, as always, can read him.

"Are you—" he stops, clears his throat. Tries again, though the words obviously pain him. "Are you expecting your... wife?"

Remus shakes his head. "She knew, Sirius. She always knew, but somehow I think she was okay with it. Maybe I'll see her again someday, but... we were never going to board the same train."

Sirius pulls him tighter, but he can't hide his grin. Remus wouldn't expect him to.

He considers, briefly, asking where the train is headed, then decides it doesn't matter. Sirius is here, and James, and Lily. Wherever they're headed, it's okay with Remus.

It ends on a train.