James rushed up the stairs to the fourth floor. He was late for detention. It was his first of the year, which was miraculous considering it was October, and he wanted to make a good impression. Especially since it was Lily who would be watching him.

He still had no idea what she would make him do, but that wasn't what he was apprehensive about. He had already done it all in the past years: lines, cleaning duty in the dungeons, cleaning duty in the second floor toilets, giving remedial classes to confused first years, dusting all the portraits in the castle, more lines and more cleaning duties.

He only dared to hope Lily wasn't creative enough to come up with something he hadn't yet been forced to do. Dealing with his sweaty palms and whatever spell she had him under would be enough work for one night. Well, one night of each week until the end of the year.

He arrived in front of the Transfiguration classroom panting, and had to take a moment to catch his breath. It had been a while since he had been in detention with someone else than a teacher and he wasn't sure if he was supposed to knock or just go in.

He settled on coming in without a warning and pushed the door which opened with a creak. Lily was sitting crossed-legged on the chair at the teacher's desk, bent over what looked like homework. Her hair was up into a messy bun and wavy strands brushed against her freckles cheeks and warm smile.

"Welcome to my honorary office!" she said, opening welcoming arms. "Glad you could join me here, I've been waiting for ten minutes and it's not as if I had anything better to do on Thursday nights than monitor detentions."

James bowed.

"Glad I can help make this evening more interesting for you."

Lily rolled her eyes and sighed dramatically. James' smile didn't disappear.

"Just... just sit down," she motioned. She looked a little tired and there were dark circles under her eyes. "Wherever, I don't care."

James chose the table closest to Lily's desk and, for the first time in his life, found himself in the first row of a classroom. He was usually all the way at the back of the room, rocking on his chair and making notes fly to his friends.

"What am I doing?" he asked as he sat down.

Lily smiled, in a more sincere way this time, and motioned to a stack of envelopes and parchment.

"Get out your quill and ink. And prepare to write. A lot."

"Lines?" said James incredulously. "And here I thought you and Minerva had more imagination."

"Oh, it's not lines," Lily answered, and somehow her smile shifted from sincere to mischievous. It was a very subtle shift and perhaps someone other than him wouldn't have noticed, but James had spent countless hours dreaming of that smile and he could read it better than anyone.

Which means he was very scared about what was to come.

"It's much better than lines actually," Lily continued. "You are writing apology letters for what happened in the Great Hall, one for each person who was there. And they all have to be personal, so you can't use banalities, I will be checking for each one."

James felt his blood freeze in his veins and for once it wasn't due to Lily's penetrating eyes. It was what she said.

"I'm not doing that," he said immediately.

"Oh," Lily raised her eyebrows and put down her quill. "See, I was under the impression that you had to do everything I said. Given you're in detention and I'm monitoring you. You know."

James bit down on his bottom lip. Apology letters? To the entire school? This had to be some sort of prank. Now he was just waiting for Sirius and Peter to jump from behind the door and laugh with him about how insane this whole thing was. Any time now.

"And you're starting with the Slytherins," said Lily calmly, returning to her homework. "You were ready to let them take the fall after all, they're the ones you need to apologize to the most."

That was the moment James realized it wasn't a practical joke after all. Lily was serious. He got up from his chair and threw his quill back in his book-bag.

"No, I won't do it, I don't care," he said as he walked away. "Even if technically I have to answer to you every Thursday night, I still have the littlest bit of pride you know, and I intend to keep it."

"Oh for the love of God, don't make this about pride!" Lily had stood up too and was standing firmly at the desk, her hands clenched into fists on the dark wood. "Because this is about sincerity. And the two don't blend well together when it comes to you."

"Was that a barely disguised insult?"

"Why, yes, I believe it was."

James walked back to his table, ready to write and prove her wrong. He grabbed his quill angrily and spilled ink all over the desk with his rough movement. Despite being furious at her, he was still thankful that Lily had enough tact to pretend she didn't notice.

"And you're starting with Severus," she said once he was done sponging all the ink with the sleeves of his black robes.

James straightened up and looked directly at her. Her eyes were serious but the corners of her mouth were lifting just slightly. She was having too much fun.

"I'm not doing that. Anything but that."

"Oh really? So, are you going to notify McGonagall you are refusing to obey me, or should I do it myself?"

"You won't go to McGonagall," said James, remembering how reticent Lily was to turning him in on the day of the fireworks. "You're too ethical."

"Too ethical?" Lily repeated, a blush slowly appearing on her cheeks. "Is that what you really think of me?"

James chose not to say anything back and just rock his chair back, crossing his arms against his chest.

"You think that because I'm a prefect I'm a goody-two-shoes abiding to a strict code of moral conduct? Really? Because you know, instead of going to McGonagall, I may just as well complain to my dorm mate and really good friend Marlene tonight. You know, the captain of the Quidditch team you're on? Then she might or might not make an important decision about your place on that same team."

"You wouldn't do that," said James, although he knew she would.

"Fucking try me."

James took a deep breath and started the letter while Lily got back to her homework, and for a while the silence reigning in the room was only disturbed by the grating of quills on parchment.

"Listen," said Lily after a few very long and very silent minutes. "The fact that this is bothering you so much just shows how much you need this."

"This?" replied James, who had just been waiting for another opportunity to manifest his discontent. "You mean humiliate myself?"

"I mean being the bigger person. Putting your ego aside for a second, acting like a reasonable adult."

"I'm not an adult though, am I?" he replied coolly. He was still angry but knew fairly well that manifesting said anger wouldn't help him in this situation. "I'm a teenager and I make mistakes like everyone does when they're young. I have the rest of my life to act like an adult, why should I start now?"

"It's an apology, James, it's not making you weaker if that's what you're worried about!"

"Well, it's not making me much stronger now, is it?"

Lily stared down at her hands she was clasping together. She looked beautiful, noted James before remembering it truly didn't matter.

"Actually, I believe it is making you stronger."

"How?"

The question was just a whisper. Lily could have easily ignored it. She didn't.

"By admitting you did something wrong. And you just have. The James I knew in first year would never have admitted fault so easily. It means you're growing up, even if you're desperately trying to prevent it."

Finally tearing her gaze away from her white knuckles, she smiled and looked up at him with wet eyes and he realized this probably meant more to her than she was letting on.

"Because we can't be teenagers forever," she continued, blinking to chase her tears. "There's a war going on, James. You know it just as well as I do. We have to grow up, whether we want it or not, and it means making sacrifices, doing things you'd never thought you'd do. It means adopting a new mindset and a new perspective on life and on the world. Yes, we're too young and no, it isn't fair. But it doesn't change the fact that becoming adults is necessary for us right now."

Lost for words, James nodded. Once again, Lily was right. Undeniably, painfully right. He picked up his quill and continued writing, laying on paper words he never thought he would.

It was hard, and he struggled at every word. He was not used to this. And considering the time it took him to write a simple line, perhaps he never would be. But he was determined to show Lily he understood what she was saying, so he kept going.

It took him about an hour of intense concentration to write ten lines that didn't feel overly insincere.

"What should I do with this?" he asked, breaking the heavy silence and pushing the letter on his table.

"Just give it to me," replied Lily. "I'm supposed to read over everything before you leave."

James approached the desk, and as he handed the parchment over to Lily, he realized that what he had mistaken for homework since the beginning of the night was actually a letter, which, according to the first few words he accidental read, was destined to her sister.

He looked up precipitately and Lily smiled at the panicked look on his face.

"Sorry I didn't mean to snoop!" he explained immediately. "I thought this was homework!"

"It's fine, you can look," Lily laughed. "It's not as if you weren't already aware of everything going on with Petunia and me anyway."

"Are things better?" James asked, looking attentively at Lily. They were separated by the desk but they were still too close for James' comfort. "With your sister, I mean."

"No," answered Lily and James pretended he didn't hear her voice break when pronouncing the word. "I think I just have to accept that my relationship with my sister will never be perfect."

"Perfect is a fantasy," they both said at the same time.

Lily laughed and James smiled. No matter how different they were, in their energies, in their goals, in their lives, they were similar at their core. The one thing that mattered most. And perhaps, there was the tiniest of possibility they understood each other.

After hearing Lily's beautiful and genuine laugh at the fact that they had said exactly the same thing, James' heart was so full he felt like it could burst at any moment.

"Go," said Lily finally. "Meet your friends, I have to finish up with my letter."

"You're not going to check mine?" asked James, pointing at the parchment Lily was holding.

She looked at it for a split second before setting it aside.

"No. I trust you."

I trust you.