It was eleven thirty at night, and a second-year Scorpius Malfoy was in an abandoned dungeon in Hogwarts castle, lit only by a single silvery globe floating above him and the small fire under his bubbling cauldron. He only wished this deliciously clandestine endeavour was for something a lot cooler than homework.

It was for Potions class, and Scorpius could've technically done this in the common room, but brewing potions outside of class was usually something only remedial students did, which was a problem because no one could know that Scorpius Malfoy needed remedial potions.

Especially not one extremely-smart-and-annoyingly-humble redheaded classmate.

Seriously, it was irritating to the highest degree. Rose could downplay herself to the depths of the Black Lake sometimes. She was funny, but she was never trying to be everyone's centre of attention, and she had opinions about everything, but she was shoving them down other people's throats, and she was so goddamn smart, but Scorpius had never once seen her become cutthroat about grades in the way that he sometimes was. She was effortlessly cool and easy-going and made Scorpius see the world with colours he'd never noticed before.

Alright, so maybe Scorpius had a crush on Rose. And maybe Potions was her best subject. And maybe it had been a tiny bit embarrassing for Scorpius to have been paired up with Rose for Potions class, knowing full well that he was horrible at it, and maybe he was trying to get better because he was desperate to earn Rose's respect and being good at her favourite subject was the only way.

Scorpius was just dwelling on this when his nostrils caught a horrible stink rising out of his cauldron. He flinched – his "potion" was a slimy black mass curdling at the bottom – how the hell did that happen?! – and the smell of something worse than dragon droppings was rapidly filling up the dungeon.

It was fine. It was fine. It was fine. Scorpius would try again.

Quickly putting out the fire and trying to disappear the monstrosity (semi-successfully), Scorpius scurried before a certain Hogwarts caretaker found him there and murdered him.

Two weeks later, Scorpius's attempts were getting better, but he was still a far cry from successful. He was bad at memorization, he'd always known that, and the irritation from reading dizzyingly absurd instructions and needing to follow them exactly made him mess up each time. So he sat next to Rose in Potions and agreed with her about everything she said. He even nodded enthusiastically. It had worked for the past two classes with no hitches at all.

"You're really not getting any of this, are you?" Rose asked.

"What? Noooo… of course I totally get it. We put the worm eyes and the – fish guts, in the –"

"They're actually toad guts," Rose said sheepishly.

"It's a thing that live in water," Scorpius waved dismissively. "Point is, continue."

Rose shook her head. "There isn't a point if you don't understand what I'm saying. We're paired up for classes, but you know we'll both still need to make separate potions for assignments, Scorpius," she said. "Maybe I could help teach you, if you wanted?"

Scorpius resigned himself to her insufferable niceness. "It's no good. I appreciate you offering but I do remedial exercises every night. I'm getting better," he said, unconvincingly.

She smiled. "Alright. I'm sure you'll be top of the class in no time."

Scorpius melted, if only a little.

Next class, Rose raised an eyebrow at Scorpius as he set his cauldron down next to her. He looked down – oh, green slime was stuck inside, from his latest attempt at a Burn-Healing Paste.

"Scourgify," he muttered hurriedly. The slime vanished, but there was still a lingering odour of bad eggs. It was truly such a nightmare that Rose possessed the senses of sight and smell.

"You know, you might be putting in too much knotgrass," Rose mused. "Its sap really makes the salve stickier instead of just thick."

"I put in ten individual leaves, just like it says," Scorpius gestured to their textbook, Magical Drafts and Potions.

"Then maybe it's too much heat?" Rose suggested. "Have you measured the thickness of the bottom of your cauldron?"

"Wait, we're supposed to do that?"

"Yeah," Rose said, amused. "You factor the size of the fire and the make of the cauldron before starting a potion. Though since we're all required to buy standard-size pewter cauldrons, and fires in classes are supervised, nobody really bothers."

"Wow, okay," Scorpius said. He hadn't been paying attention to size of the fire he lit in the dungeons at all. "But this isn't mentioned in the textbook."

"Not in the recipes for individual potions. It's in the foreword."

"Who reads the foreword?" Scorpius scoffed, then immediately stopped when Rose rolled her eyes.

"Right," he cleared his throat. "Thank you for helping."

"You're welcome."

That night in his usual dungeon, Scorpius diligently followed Rose's lead, and read the foreword of his Potions textbook. Or, to be more accurate, he tried to.

He had a growing hatred for the subject, even more than his previously most-hated subject – History of Magic. Both required pure memorization, but at least forgetting Grunthill the bum-scratching Goblin's sixth strike on who-gives-a-damn didn't turn anything into a foul-smelling and potentially dangerous mess.

This foreword had to be the most banal piece of writing ever conceived by a living thing, he decided. He trudged through it; the author was droning on about the importance of not scrubbing your cauldron too hard while cleaning as it might offset calculations of its heat conduction capability – his thoughts were wandering in the background like bees buzzing – Scorpius' potions were stinky, poisonous, and unusable. They were going to stay that way no matter what torturous writing Weasley gave him to read. He should've asked to be reassigned to someone else right from the start to avoid embarrassing himself. Thinking that he could ever have self-studied to get better at this was so stupid. People either had a knack for potion-making or they didn't, and Scorpius clearly –

Footsteps.

Scorpius shut the book and turned off the light in a swift second before someone's lit wand appeared around the corner. He slunk into the shadows near the wall as two people walked steadily towards him, engrossed in a whispered conversation.

Scorpius held his breath, straining to listen to their conversation. Now that they were close enough for Scorpius to make out their silhouettes, they seemed like students too.

"Oh hey Scorpius, what are you doing here?"

Scorpius blinked at the lit wand in his face. "Rose?" he sputtered.

Damnit, did this girl miss nothing?

"Oh, sorry," Rose lowered her wand, and Scorpius saw that she was with another girl from their year – Mavis Longbottom.

"Uhh, what are you doing here?" He countered, unable to come up with anything better. Only Rose knew about his remedial classes, but he was friends with Rose (while also being secretly in love w– wait what?) Anyway, the damage was done, he sounded like an idiot.

"I guess, we won't say anything if you won't," said Mavis generously, after an awkward pause. Scorpius shrugged his assent.

"Actually, why don't you come with us?" said Rose, a soft smile tugging at her lips.

"For that, you'll have to tell me where you're going," Scorpius narrowed his eyes.

"Come on, you'll see it in a bit," she insisted. "Don't you trust me?"

She had him there.

They were going to the edge of the Black Lake. Rose and Mavis led him through a secret passageway out of the dungeons, onto the castle grounds.

"I thought they'd sealed off all secret passageways before the Battle of Hogwarts," Scorpius muttered.

"Only the ones that led out of the castle grounds, to Hogsmeade or elsewhere," Mavis said. "There are a bunch that only lead out of the actual castle, into the grounds. And we," she gestured between Rose and herself, "have discovered quite a few of them."

"Passageways apart from all the windows on the ground-floor, you mean?" Scorpius asked, grinning.

"You can't leave through the windows," Rose giggled, "they're enchanted. As we found out to our immense dismay last year."

Scorpius smiled. "What'd you do?"

"We tried to jump out of one," said Rose. "We broke the glass, and all this red smoke showed up, and we fainted. Woke up in the hospital room with a very angry Headmistress."

"And my Dad," said Mavis. "He was alright, though. Just told us to not try it again 'cause it's not safe."

"Yeah, our folks got pretty paranoid about security after the Battle," said Rose. "Did you know the whole Lake is enchanted? You can't swim across it, the merpeople find out and stop you."

"There's merpeople in the Lake?" Scorpius asked, amazed. "Also, have you tried to swim across the Black Lake?"

"Only twice," Rose smirked. "Speaking of…"

They arrived at the Boathouse, the little dock and accompanying shack where the boats with the first-years landed every year at the start of term. The lake was a still mirror that night, stretching forwards until you could see the dim lights of cosy Hogsmeade on the other edge. Rose and Mavis ducked inside, fetching cauldrons from the cupboards.

"Wait," said Scorpius. "Now we're here. What are we doing?"

"Your favourite activity, Scorpius," Rose said with a truly shit-eating grin. "We're brewing a potion."

"What the hell? For class?" Scorpius really thought that the night was finally getting strange, even for him.

"No, are you crazy?" Mavis said, now assembling ingredients. "What kind of people did you think we are?"

"Normal?" He suggested. "Who brews potions for fun?"

"I'm disappointed," Mavis replied. "Anyway, hand me the asphodel."

So Scorpius did, and he didn't really have a choice but to stick around, did he? He had watched Rose in Potions classes for over a year, but it was never like this. She was having fun with ingredients now, experimenting and inventing, discussing the pros and cons of trying this or that with Mavis with rapid-fire reasoning.

Scorpius didn't know what they were making, but he wasn't in a hurry to find out. He sat with them on the moonlit floor and felt himself enjoying listening to them argue about how x ingredient might react with y, or if they should try a spell, or how a different book had suggested some better way to stir or strain or cut or cast something.

After poking and prodding the solution for about a half hour, both Rose and Mavis looked satisfied. Scorpius wondered what was in store.

"Ready?" asked Rose, levitating the cauldron full of the mysterious potion in front of her.

Scorpius stood up and followed them to the edge of the water. In the light of the full moon, Scorpius saw Rose carefully levitate the solution so it wouldn't spill, making it float far out ahead of them, reflected on the glassy surface. Then, slowly, she poured it into the Lake.

At first, nothing happened.

Rose brought her cauldron back, and just as Scorpius was about to ask, he noticed it. A sort of silvery glow had appeared where the potion had sunk, brightening the water like bioluminescent fish.

The glow trickled out in tendrils, like honey being poured in water, sinking deeper and covering the surface of the lake like a sunset, until it was shining with a light of its own from within. Scorpius was breathing hard in the chill breeze coming off the water – and he had never seen anything look so beautiful.

Rose picked up a pebble, and skipped it across the water. The shock of it made the glowing tendrils quiver and change direction, looking like silvery fractal art.

Scorpius cheered and picked up his own, soon getting into a contest with Rose about who could get the most pebble skips. Mavis levitated a huge boulder and let it plop into the centre of the lake, creating a massive ripple that spread out the silver fire even more.

Scorpius couldn't stop staring.

"So, what exactly did you do?" He eventually asked Rose and Mavis, sitting down by the edge of the water with them. Mavis was lying on her back, looking up at the stars, while Rose was hugging her knees, a huge grin on her face.

"Grindylow eggs hatch on the first full moon after the solstice, twice a year. That is today." Rose said, pointing up. "And we used Grindylow eggshells in that potion last week about making Everlasting Lamps, so Mavis and I wondered, if we could somehow use the bits of eggshells floating in the water today, to turn the Lake into some sort of a giant lamp, basically. And look!" Rose looked indescribably pleased with herself, more than Scorpius had ever seen her before.

Scorpius marvelled at her for a second before a thought struck him. "So, this is everlasting?"

"Uhhh," cut in Mavis, eloquently. "We're not sure."

"Not sure?" Scorpius couldn't help but laugh. "You two are really begging for detention."

"We three," Mavis corrected. "If we go down, we're taking you down with us."

"Pleeeease," Scorpius said. "Like anyone would believe I could make that happen," he gestured to the Lake.

"What do you mean? You're brilliant in class, Malfoy," said Mavis, so matter-of-fact that Scorpius blinked, owlishly.

"…not in Potions," Scorpius admitted, feeling embarrassed. "I'm absolutely horrid. In fact, I do remedial exercises in that dungeon every night."

"How are they going?" Mavis asked.

Scorpius glanced at Rose, who was clearly listening, but staring over the lake, not putting him on the spot.

"I'm bored to death and about to flunk?" He winced.

"Ah, that's alright, Scorpius," Mavis said kindly. "You know, I'd be happy to help you if you want any, or Rose too." Rose nodded her agreement.

Scorpius had thought admitting his failure would've been hard for him, but around Mavis and Rose, it had been much easier than expected. Perhaps accepting help would be less difficult than he had imagined, too.

"I'd really like that," he admitted.

A week later, Scorpius was studying in the library with Rose, who was sitting in a chair beside him with her legs folded up in truly impossible twist, reading her way through a chapter through her History of Magic textbook. Scorpius was ignoring the tug at the corner of his lips, begging a smile. He was here to concentrate on Potions.

"Maybe you should know what you're putting in your cauldron before you go and do it," Rose had advised, handing him a copy of One Thousand Magical Plants and Fungi.

It's not that Scorpius hadn't tried to read the book before – it was assigned to all first-years. It was just his usual problem – it was boring and Scorpius sucked at memorization. His dubiousness about the results was justified, he thought.

The book was essentially a glossary of terms, so the going was slow. Every couple of words, Scorpius would look up, and catch Rose in the middle of her own work. Her presence encouraged him, gave him the necessary motivation to actually pay attention to what he was doing.

Instead of going in alphabetical order, Scorpius started by looking up ingredients he already knew. After he had looked up 'Aconite', 'Gillyweed', and 'Hemlock' without once breaking focus, he reached 'Knotgrass.' It read, 'Knotgrass is a highly versatile ingredient in potion-making, known for its soothing properties, which makes it especially important in most healing and cosmetic potions. It is also extremely water-absorbent, meaning that it will soak up moisture from its surroundings very quickly.'

The water-absorption property started to make sense to Scorpius as he thought about the slimy, jelly-like consistency of his first few tries on the Burn salve that had used knotgrass. He looked up excitedly to share this observation with Rose when he noticed for the first time that she'd fallen asleep.

Her cheek rested on the desk, hair cascading behind her. Rose's legs were crossed in the chair under her and her quill was still held between her fingers, albeit at a jaunty angle. Thoughts flitted through Scorpius – stealthily drawing on Rose's face, waking her up to insist that she go back to her dorm and sleep, or shrieking in her ear to startle her – but Scorpius did none of those things. Rose's decision to doze off rather than go back, for his sake, flooded him with warmth. Scorpius reached out and gently touched one of her curls with fondness, making Rose sigh a little. Smiling, Scorpius withdrew his hand and curled up in his own chair to continue reading.

"…And one last stir, aaaaand that should do it!" said Scorpius, lifting his ladle out of the cauldron with a flourish, extinguishing the flame under it with a wave of his wand.

"Very good!" exclaimed Rose, delighted. Scorpius had asked Rose to oversee his potion-brewing on one of his usual late-night practise sessions. "This should get you a really good grade, Scorpius. And plus, Slughorn is already so impressed with your improvement," Rose beamed.

"Thanks," said Scorpius, blushing a little. "But I know it's not perfect, look, isn't it supposed to bubble for 5 minutes before turning silver? It's already stopped moving," he pointed out.

"Yeah, it is" Rose agreed. "You were doing perfectly until you added just a smidge more of Horklump juice," she said. "But it doesn't change the properties of the potion much, even though it doesn't look exactly how it's said to in the book. You've got nothing to worry about, your potion is amazing."

And Scorpius believed her. The relief of success washed over him, stronger than he'd anticipated. He hadn't been able to get this right for so long, but with Rose helping him, it had almost felt too easy. She caught his eye just as this thought crossed his mind, and unable to hold back, he reached out for her waist, hugging her close.

"Thank you," he said, more earnestly than he'd ever expressed gratitude before.

"I didn't even do anything!" Rose giggled pleasantly against his neck, looping her arms around his neck and holding as tightly and he was holding her. "But I'm not complaining, so, you're welcome."

Scorpius' heart was beating a little fast. He allowed himself a second, exactly one second more than necessary to stay like that, with Rose in his arms.

When Scorpius got his grade for the next Potions assignment, he was shocked at how well he'd done. For the first time, he felt happy for the thing in and of itself, not feeling a need to compare himself to everyone else who took the class with him. And Rose's squeals of joy and affirmations of pride – well, that felt like more than what he could ever need to feel like he was enough.