"Pete!" James bounded on to Peter's bed, the rush of air from his movement sending Peter's quill scrawling across the page. "What's Moony's favourite chocolate?"

"The nutty ones from Honeyduke's," Peter answered automatically, trying to blot up the ink with his sleeve. "I'll never get this essay finished now..." Startling upright, leaving the ink to soak into the parchment, he turned to look suspiciously at James. "Why do you want to know Moony's favourite chocolate anyway? Are you apologising for something? Did Sirius do something?"

"Why do I have to be up to something to want to know the favourite chocolate of one of my friends?" James looked wounded, clutching his chest. "I can't have just genuinely forgotten?"

"Why do you even know that?" Sirius asked from his position hanging upside down from the side of his bed. He wriggled his shoulders, hair brushing back and forth across the floor. "You didn't even have to think about it. You just knew."

Peter looked confused. "Remus is my best friend. Of course I do."

"I don't know. I think I'd at least have to think about it," James said thoughtfully. "I don't think I could tell you Sirius' favourite ice cream flavour straight up like that."

"What about you, Pete?" Sirius swung himself upright, eyes sharp. "What's Remus' favourite ice cream flavour?"

Peter looked nervously back and forth between the two of them. "Uh, caramel fudge is best, but never anything with chocolate in it, because chocolate in ice cream doesn't taste right." The other two boys looked surprised for a minute, and Peter's expression became even more uncertain. "Didn't you know that?"

Remus entered the dorm, interrupting what was sure to be an awkward conversation.

"Hey Moony," James asked as soon as he saw who had just entered, "what's Pete's favourite ice cream flavour?"

"Raspberry peppermint," Remus answered promptly. "He likes how fresh it tastes. Why?"

"How do you just know this?"

Remus looked just as confused as Peter had moments earlier. "Because we're best friends. Why are you asking such weird questions?"

"That's not what best friends are like." Sirius shook his head. "James and I are best friends, and we're not like that."

"Couldn't there be different types of best friends?" Peter tentatively put forward.

"Best friends do anything for each other, know what each other are thinking, like to do the same things, and do them together," Sirius continued, disregarding Peter's suggestion. "They don't know silly little details about each other!"

"Maybe some best friends do!" Remus retorted, an edge starting to seep into his voice.

"Remus is just like that, though," Peter hesitantly volunteered. "He's observant about things."

Remus smiled gratefully at him. "So're you, Pete. That's probably why we make good friends."

"Best friends," Peter corrected.

Remus' smile widened. "Best friends."

Peter glanced over at James and Sirius, who had become bored of the conversation and were now loudly planning how they might make ice-cream rain from the ceiling of the Great Hall. He turned back to Remus, saying quietly, "And I'm not going to ask anything about the secret you're keeping."

Remus' face abruptly went white. "Se-secret?"

"I know you aren't going to your mum's, and I know every month you get really sick, then go away and come back injured." Peter quirked a smile. "We're the observant ones. I don't know what it all means, and I'm not going to try and find out, but I couldn't help but notice."

"And the others?" Remus asked breathlessly, still too caught up in worry to even be grateful Peter wasn't going to push him.

"James and Sirius haven't noticed anything," Peter told him. "But they'll figure it out eventually, you know. You should just tell them now."

Remus shook his head miserably. "I can't. They'll hate me. You," his voice caught, "you all will."

Peter hesitated for a moment, then reached out, grabbing Remus' hand and squeezing it. "I'll never hate you. You can tell me anything, Remus. Even if you…" His eyebrows scrunched together as he tried to imagine the worst possible secret Remus might be keeping. "If you were a Kneazle in disguise! You'd still be my best friend."

"Thanks, Peter." Remus tried to smile, but his eyes gave him away.

Peter squeezed his hand once more before letting go. "You're my best friend," he repeated. "Whatever you're afraid of, you can trust us."

This time, Remus' smile looked slightly more real. "I'll try."