A/N: Wrote this...gosh, probably two years ago. Finally decided to start cleaning out the ol' fic folder and post some of it. This is basically just a snippet of my headcanon, but it's something.

It takes six and a half days at Hogwarts for Remus Lupin to admit that Sirius Black and James Potter are funnier than they are aggravating, and by the time he's changed his mind again it's too late.

Three more days and he's bringing them the books they've left behind in their mad rush to breakfast.

"Thanks, Professor," Peter Pettigrew snorts, glowing when James gives him a small, approving grin.

Sirius looks horrified. "Remus would never! He's on our side."

He takes the book gratefully anyway. They all do. Remus laughs along and enjoys his pancakes.

Professor Lupin. Really.

It's a month before he lets them drag him into a prank and two before he plans one.

"We could change the weather in the Great Hall. Make it real," says Remus, hoping the others won't notice that the suggestion is neither practical nor, he assumes, particularly original. He isn't used to mischief yet, and it feels a bit like jumping out of a tree because a bird said flying was easy.

Peter frowns. "What if it rains?"

"Well, that's sort of the point, you see," says Sirius. "Slytherins get wet. I'm in, Lupin." Sirius has a peculiar habit of calling them all by their surnames when they're up to no good. Remus suspects it's because he fancies himself a pirate or something, and in Sirius's mind that's probably what pirates do.

"But what if we get wet?" James asks, and they all frown. It's hard enough to do a spell on that scale without trying to localize it.

Remus finds the answer in one of his Charms textbooks a week later. "I've got it!" he shouts, and James grabs the book and practically squeals with glee. (They promise never to tell that part. Naturally, Sirius imitates him at every possible opportunity, following it each time with, "But I didn't know Evans was there!")

It's a success. Sirius swears even Professor McGonagall smiled a bit as dark clouds gathered over the Slytherin table, and Peter bursts into spontaneous laughter for a week when he remembers Severus Snape's face when he and his textbook were drenched. (Remus feels bad for that one; he didn't mean to do any real damage, and textbooks are expensive.) Dumbledore secretly awards them five points each after Professor Slughorn takes ten; it was an impressive feat for four first years.

James muses dreamily that they might have avoided detention entirely if they'd added the lightning he wanted. Remus points out that expulsion seems more likely, but he has to admire the mental images the idea produces. Sirius's horrid cousins with singed hair are a sight he'd like to see.

He tries so hard not to become attached to them, but by Christmas he's admitted it's pointless. He's hopelessly in love with Hogwarts and Gryffindor and his new life, even if he still thinks he doesn't deserve any of it.

They're bound to figure it out—they're idiots, but they aren't stupid—and they'll probably hate him when they do. No, they'll certainly hate him. But they haven't left him yet, and before long he gives in and decides to enjoy it while it lasts.

By the time Easter has come and gone, he's given up reprimanding them for sneaking to the kitchens to bring him chocolate cake in the hospital wing. He stops complaining every time Sirius sits at the foot of his infirmary bed and doesn't shut up till Remus falls asleep.

Two weeks before exams, he tells them. He nearly has a panic attack before it all just spills out.

"I'm a… a werewolf. I'msorrypleasedon'ttellanyone." He squeezes his eyes shut.

It's a whole minute before he dares to look at them and learns they've known for quite some time.

("Remus, we've been charting the moon in astronomy all year."

"Yeah, we were bound to notice sometime."

"We think it's brilliant!"

"Have you got really enormous fangs? Ouch, what was that for?")

He never quite stops being shocked by the way James and Peter grin and shake their heads, just the way he always does when they're being particularly thick. Or the way Sirius just winks like he knew all along.