HP: Those Years Sleeping with the Half-Blood Prince

Severus glanced at him quickly. "Until the investigation is over, you're nothing."

He turned back and continued walking forward, his tone returning to its usual calm, "Moreover, the improvements are not yet perfect, and it's still a long way from a truly stable and usable formula."

"Then let's keep refining it." Ian followed him, his tone relaxed. "Anyway, we still have the materials and the time. Maybe the association will allocate some research funding after the paper is approved?"

Severus didn't accept this overly optimistic assumption, but his body wasn't as tense anymore.

That evening, in the Room of Requirement, Severus was unusually silent, spending most of his time repeatedly checking the experimental data and draft papers on the moderating agents, occasionally writing a few words on parchment and then crossing them out.

Kevin was catching up on the homework that had piled up during the holidays, sighing and complaining.

Aris, on the other hand, is researching a complex runic encryption system that is said to be able to add a "physical firewall" to their ledger.

Ian leaned back on an old sofa, holding a book about the changes in African magical plant communities, but seemed somewhat distracted.

He thought about Slughorn's words, the paper submitted for review, Regulus Black's hint of a "common goal," and the silent ripples in Severus's eyes.

He knew that some things were like undercurrents at the bottom of a lake, calm on the surface but already surging deep within.

"Oh, right," Kevin suddenly looked up from a pile of dusty old papers, rubbing his sore eyes, "Have you heard? Ravenclaw's Seeker, the seventh-year guy who always wears those crystal glasses, fell off a broom during practice and sprained his wrist. Mrs. Pomfrey says he'll be out for at least a week. They're playing Hufflepuff next week, and they're jumping up and down in a panic."

Aris, without looking up, said, "Based on the current situation, their substitutes are clearly not up to par, and there's a high chance they'll contact us before next week."

Ian closed the book and looked at Severus. "Is the stock enough? The Ravenclaw captain seems to be quite particular; he might want a version that's more effective and has fewer side effects."

Severus looked up from the parchment and nodded. "There's a backup, enhanced version that's even better at relieving pain and reducing swelling, but it costs 30% more."

"Then sell it to them at a 50% premium," Ian said decisively. "Just say the materials are rare, the failure rate in refining is high, they're in a hurry and won't haggle."

Kevin whistled. "Ian, you really have a knack for business."

"It's just a mutually beneficial arrangement." Ian smiled, but his gaze drifted back to Severus.

Severus had lowered his head again, the quill pen tip gliding across the paper with a soft rustling sound.

The Room of Requirement returned to silence until Kevin let out an exaggerated yawn, signaling that his mental energy for the day was completely depleted. The group then packed up their things and returned to the cellar.

The next few days passed as usual.

Courses, assignments, Quidditch practice, and the occasional needs of those "small businesses".

Severus seemed no different from usual, still the most silent figure in the classroom and library, his performance in Potions class was impeccable, even more precise.

But Ian still noticed a subtle difference.

Severus's eyes occasionally showed faint bluish-black tinges, not from staying up late to read, but more like the weariness of having his energy invisibly depleted.

His fingers would sometimes pause slightly as he turned the pages, as if he were enduring something.

In the Room of Requirement, he spent more time fiddling with the instruments and brooches, but occasionally a hint of confusion would appear on his face.

More importantly, Ian noticed that Severus was more cautious than usual when handling certain magical materials, especially those with cold or gloomy properties or those with a slight spiritual influence. He was even overly cautious.

Once, Aris accidentally knocked over a small bottle containing armadillo bile. Severus took a step back almost the instant the bottle tilted. Although Kevin caught the bottle with lightning speed, Ian noticed Severus's tense body and sudden sharp gaze.

"Haven't been sleeping well lately?" Ian asked casually at breakfast, handing over a plate of bread.

Severus paused as he took the bread, lowering his eyelashes. "A little. I'm adjusting a potion recipe; the dosage is a bit tricky."

"Don't overexert yourself," Ian said, taking a sip of milk. "Professor Slughorn is counting on you to bring honor to his club."

Severus grunted in response and said nothing more.

But things are clearly not that simple.

A few days later, late one night, Ian was awakened by a slight rustling sound of fabric.

The sound came from Severus's bed across the way.

Ian opened his eyes in the darkness and saw that the curtain on Severus's side was slightly drawn back.

Severus sat on the edge of the bed with his back to him, head down, shoulders slightly hunched.

He seemed to be doing something with his left hand, the movement was very light, with a deliberately suppressed stiffness.

Ian watched quietly for a while, until Severus seemed to have finished, quickly stuffing a small bottle back under his pillow and pulling the curtains tighter.

The dormitory fell silent again, with only Kevin's even breathing sounding.

The next day, during Transfiguration class, Ian "accidentally" knocked over a bottle of ink on the table on Severus's side.

Severus reacted quickly by pulling out his parchment, but Ian's hand was already faster, grabbing a rag to wipe it.

"Sorry," Ian said, his fingers "accidentally" brushing against the back of Severus's left hand, which was resting on the edge of the table.

The touch felt wrong, and Severus quickly withdrew his hand as if burned, stuffing it into his robe pocket.

Ian wiped the table clean with a normal expression, but his heart sank.

A curse backlash? Or did something go wrong while researching the brooch? Given Severus's personality, he would never speak unless absolutely necessary.

He wanted to know what had happened.

……

After Friday's Potions class, Professor Slughorn kept Severus behind again.

Ian waited in the corridor for nearly twenty minutes before Severus came out, looking paler than usual.

"The professor's enthusiasm is really hard to resist, isn't it?" Ian said as they walked, naturally taking the heavy reference books from Severus's arms to help him carry them. "You don't look too well lately. Is it because Professor Slughorn is pushing you too hard? Or..."

He paused, lowered his voice, and said in a volume only the two of them could hear, "That little thing is getting restless?"

Severus hesitated for a moment.

He didn't answer immediately. Several seconds passed, and just when Ian thought he was going to remain silent again, he uttered a very soft sentence, with a hint of barely perceptible frustration.