Harry sat near the back of the Defense Against the Dark Arts classroom, watching Gilderoy Lockhart, who was holding up Year with a Yeti and regaling the class with another one of his wildly embellished stories. Harry had been skeptical of Lockhart ever since he'd first seen his books in Diagon Alley, and today's lecture only confirmed what he already knew: Lockhart was a fraud.

"The yetis of Tibet," Lockhart began, his voice filled with dramatic flair, "are some of the most dangerous creatures I've ever encountered. During a particularly harsh winter, they were driven down from the mountains, desperate for food. The villagers were utterly helpless—until I arrived, of course."

Harry kept his face neutral, though inside he was incredulous. Yetis, according to what he'd learned, were intelligent and peaceful, perfectly capable of surviving harsh winters by eating entire trees and using snow for hydration. The idea that they'd be desperate enough to attack a village for food was ridiculous. But Harry didn't need to call out Lockhart—he was content to let the story unravel on its own.

Lockhart continued, oblivious to the holes in his tale. "The yetis were about to tear through the village, but with quick thinking and a few well-placed spells, I managed to drive them off. It was a close battle, but naturally, I prevailed!"

Terry Boot raised his hand. "Professor, don't yetis usually stay in the mountains and avoid humans? Wouldn't they be able to find food up there, even in winter?"

Lockhart's smile flickered briefly, but he recovered quickly. "Ah, yes, Mr. Boot, ordinarily, yetis do avoid humans. But this winter was unusually severe, and they had no choice but to come down in search of food."

Harry noted the uncertainty in Lockhart's answer but remained silent. He knew yetis wouldn't starve, no matter how bad the winter. They were better at surviving those conditions than humans. Lockhart's explanation didn't hold up, but Harry wasn't about to point that out—he was more interested in seeing how the professor handled the next round of questions.

Padma Patil raised her hand next. "Aren't yetis resistant to magic? How did you manage to drive them off?"

Lockhart's smile faltered for just a second. "Ah, Ms. Patil, an excellent question! Yetis do have some resistance to magic, but with quick reflexes and the right spells, you can outmaneuver them. I used a Stinging Hex and Expelliarmus to disorient them."

Harry almost snorted. A Stinging Hex against a yeti? That would be about as effective as tickling it with a feather. He glanced around, noticing that a few of his classmates were beginning to frown. Clearly, Padma wasn't the only one unconvinced.

Harry stayed quiet, content to observe as Lockhart dug himself deeper. The professor's excuses were becoming increasingly flimsy, but his confidence never wavered. Most of the class still seemed captivated, but a few, like Terry and Padma, were clearly starting to catch on.

By the time the lesson ended, Lockhart had wrapped up his tale with another flourish, claiming that the villagers had praised him for his bravery. As the class filed out, Harry, Terry, and Michael exchanged knowing glances.

As they walked toward their next class, Terry muttered, "Does he really expect us to believe a Stinging Hex would work on a yeti?"

Harry smirked but didn't say anything. Lockhart's lies were obvious to him, but he didn't need to point them out. It was only a matter of time before everyone else realized the truth.

—

Harry sat at a wooden table in the Hogwarts library, surrounded by towering shelves of dusty tomes and scrolls. The soft glow of a nearby lamp illuminated the pages of Advanced Magical Theory, where he was finally delving into a subject that had always been deemed too advanced for his level: Extension Charms.

As he read, Harry's mind began to race with the implications of a concept central to these charms: expansion factors. The idea was simple: doubling the interior dimensions of an object meant it had an expansion factor of two. He decided to run a quick Fermi estimate in his head—a technique Gellert had often used when explaining concepts in magical theory to him. It was a simple way of breaking complex problems down into manageable estimates.

He thought about an average trunk, roughly a cubic meter, and a typical room, easily approximated as ten meters on each side, giving it a volume of a thousand cubic meters.

He knew that smaller items usually had higher expansion factors, so he reasoned that a trunk might have an expansion factor of five, resulting in an internal volume of five cubed. Meanwhile, the room, with an expansion factor of two, would yield an internal volume of twenty cubed.

The significance of the numbers became clear. While the room could fit a thousand trunks based solely on exterior measurements, only sixty-four expanded ones would fit without compressing their contents. The magic could squeeze inanimate objects without damaging them, but just like a Shrinking Charm, this squeezing effect didn't work on living things.

The quiet of the library was interrupted only by the faint scratch of a quill somewhere in the distance. The scent of old parchment hung in the still air. Suddenly, a chill ran down Harry's spine as he recalled packing for his summer travels—folding his tent into his rucksack. He had briefly considered putting Hedwig inside the tent for the journey, thinking it might be more comfortable for her.

The implications hit him hard. That was what Grindelwald had meant, the larger expansion factor of the folded tent would not have aligned with the smaller factor of his expanded rucksack. The interior of the tent would have squeezed down to the size of the interior of his rucksack. With all the furniture inside the tent, that would have been like putting a piece of fruit in a Muggle hydraulic press—his owl being the fruit. The gruesome image made his stomach turn uncomfortably.

He thought of Hedwig, her unwavering loyalty. Harry had been raised to believe that those who were loyal to him deserved his protection. A wave of responsibility settled over him. With newfound determination, Harry decided to always make careful calculations before nesting expanded objects in the future.

As he closed the book, the soft thud barely broke the stillness of the library. The unease lingered—he had nearly made a deadly mistake. That lesson would stay with him.

—

The common room pulsed with the vibrant energy of crackling flames and the spirited chatter of students winding down from the day's events. Fred and George Weasley nestled into well-worn armchairs near the fire, their eyes scanning the room with an eagerness tinged by an undercurrent of anxiety. After their meeting with Harry, a mix of apprehension and determination hung in the air like a heavy fog, for they understood the gravity of the task that lay before them.

"Where's Ginny?" Fred asked, leaning forward, his brow furrowing with concern. "She was supposed to be back from dinner by now."

George shrugged, his mind racing with thoughts of the ominous enchanted diary. They needed to approach her with care. "Maybe she's up in the dorms. We should grab her before she gets lost in a book."

As if summoned by their conversation, Ginny entered the common room, her hair damp from the rain outside, several books clutched to her chest. She looked around, her gaze flitting over the familiar faces, yet George noted a spark of mischief in her eyes, a glimmer of the playful spirit that often belied her resolve.

"Oi, Ginny!" Fred called out, a grin breaking across his face. "Come here for a minute!"

She hesitated, suspicion weaving its way into her expression before approaching. "What do you want?" she asked, a hint of defiance coloring her tone.

George exchanged a quick glance with Fred, the weight of their task settling heavily upon him. "We were just wondering if you've seen anything strange lately, like, say, an enchanted diary?"

Ginny rolled her eyes, her dismissive demeanor betraying her unease. "What? No, I haven't seen anything like that. Why do you care?"

"Because it's serious, Ginny," Fred replied, his voice lowering in earnestness. "That diary is a Dark Artifact, a dangerous piece of magic that Lucius Malfoy has planted on a student. If you have it, you need to tell us. We're not joking around."

Her eyes narrowed, and George could see the defensiveness rise within her. "You're just trying to prank me again! If I tell you I've got something, you'll just take it away! You've always done that!"

A knot of concern tightened in George's stomach, awareness flooding him with regret. He remembered the countless times they had playfully pilfered her diaries, their intentions light-hearted yet callous. The repercussions of their pranks loomed larger now, overshadowing the innocent mischief of their youth. "Ginny, this isn't a joke," he insisted, striving to keep his voice steady. "We truly want to help. If something starts acting strangely or if anyone is bothering you, you need to tell us."

She shook her head vehemently. "No! You're just trying to trick me like you always do. I don't have anything weird! Just my school books, and you're not taking them!"

As she turned away, determination in her stride, George felt a pang of guilt settle deep within him. He understood why she distrusted them; their relentless pranks had chipped away at her faith, leaving her to believe they were always out for a laugh. This time, however, the stakes were far too high. There was a real danger lurking, and she remained blissfully unaware.

"Looks like we have a lot of watching to do," Fred remarked, his earlier excitement dimmed by the weight of their conversation. "Let's keep an eye on her and see what she's up to."

"Good idea," George replied, the words heavy with unspoken resolve. "We need to be ready for anything."

As Ginny moved away, George leaned back in his chair, the burden of their past antics settling over him like a shroud. If there was a chance that Lucius Malfoy had planted something dangerous in their midst, he would do everything in his power to protect his little sister. Yet first, he realized, he would have to earn back her trust.

—

The faint click of the trunk's latch echoed through the quiet Charms classroom. Filius Flitwick watched closely as Harry slumped back into his chair, his wand resting limply on the desk. The boy's face showed the telltale signs of magical exhaustion—a furrowed brow and slightly pinched expression. He had pushed himself hard, perhaps too hard.

Flitwick felt a surge of both pride and concern. Perpetuo Vinctum was an advanced piece of magic, even for older students, and Harry had handled it with remarkable skill. But the strain was clear. "That's excellent work, Harry. Remarkable, truly," Flitwick said, his tone careful. "But I think that's enough magic for today."

Harry nodded, clearly worn out. "Agreed," he muttered, rubbing his temples. The intensity with which the boy approached his lessons never failed to impress Flitwick—pushing himself far past the point where most students would stop.

Hoping to offer a reprieve, Flitwick smiled and took a seat beside him. "Why don't we spend the rest of the time discussing theory?" he suggested lightly. "It might be less taxing after that hard work."

Harry gave a small nod, his gaze drifting to the enchanted trunk on the desk. "There's something I've been thinking about," he said casually. "We're given objects like trunks and tents that use Expansion Charms, but no one tells us how dangerous they can be if they're nested."

Flitwick's brow furrowed. It was unusual for a second-year to think about such risks. "That's an important point," he acknowledged. "Most Pureblood families teach those safety concerns early, long before their children come to Hogwarts. We tend to assume that knowledge is in place, but clearly, it's something we've overlooked."

Harry remained quiet, but Flitwick could see the boy's frustration beneath the calm exterior. It wasn't just about spells or theory—it was about practical safety.

"You've raised an important issue, and I'll make sure it's addressed," Flitwick continued, understanding now the broader implications. "Students should know how to handle these enchanted objects safely, even if they aren't casting the charms themselves."

Satisfied with the response, Harry gave a nod, but his curiosity hadn't waned. "I've got another question," he said. "About Stasis Charms."

Flitwick's interest piqued. "Ah, Stasis Charms! What would you like to know?"

"I was wondering how they interact with Expansion Charms," Harry began. "Expansion Charms create pocket dimensions, but Stasis Charms freeze time. Is that how magical freezers work? You wouldn't need to cool anything if you could keep it in stasis."

Flitwick smiled, impressed by Harry's sharp reasoning. "That's precisely it. When combined, Expansion and Stasis Charms are often used to store perishables. The Expansion Charm provides the space, while the Stasis Charm freezes time, eliminating the need for refrigeration."

Harry considered this for a moment before asking, "What happens if you put a living creature inside one of those stasis bubbles?"

Flitwick paused, weighing his words carefully. "That's where it becomes more complicated," he said, his tone more serious. "Stasis Charms stop time for whatever is placed inside, including living creatures. They wouldn't age or experience the passage of time, but they'd also be entirely unconscious—frozen in place. It's relatively safe for short-term transport, in medical emergencies for example, but for anything long-term?" He shook his head. "There are risks. Prolonged stasis can disrupt the creature's natural magical rhythms, and the longer they remain in that state, the greater the danger."

Harry nodded slowly, absorbing the explanation. "So it's only used when absolutely necessary."

"Exactly," Flitwick replied, impressed yet again by Harry's sharp perception. "It's a powerful tool, but one that requires careful judgment."

Harry leaned back in his chair, exhaustion finally overtaking his curiosity. "Thanks, Professor. That clears things up."

Flitwick smiled warmly. "Anytime, Harry. Now, you should get some rest. You've more than earned it today."

—

Harry stood in the dim quiet of the Ravenclaw library, his eyes scanning the shelves where older students kept the Owl order catalogs meticulously organized. The smell of parchment and ink filled the air, along with the faint mustiness of old books. He reached for a well-worn catalog, flipping through the pages until he found what he was looking for—a listing for portable magical freezers.

His gaze settled on one in particular: durable hardwood construction. There would be plenty of capacity in such material for further protections, in addition to built-in Stasis and Expansion charms. He memorized the shop's address, feeling a little more at ease now that he had confirmed with Flitwick that these freezers worked exactly the way he assumed—stasis, not cold.

Sliding the catalog back onto the shelf, he quickly made his way back to his private room in Ravenclaw Tower. The weight of the discovery he had made in the Room of Requirement still hung heavily on him—Ravenclaw's Diadem, tainted by something dark, something unmistakably connected to the necromancy he had sensed around Quirrell the previous year.

Sitting at his desk, Harry set about penning the order. He pulled out a piece of parchment and dipped his quill, then rapidly scratched out a concise letter to the shop requesting the freezer. His handwriting was small, neat, and precise. After sealing the letter, he rummaged through his trunk until he found an empty leather pouch and the necessary Wizarding currency. He tied it securely with a piece of twine and placed it alongside the letter, ready to be sent.

With everything ready, Harry headed out of his room, making his way through the quiet halls of the castle until he reached the Owlery. Hedwig greeted him with a soft hoot as she perched elegantly on a nearby ledge. Harry smiled and scratched behind her head before gently tying the letter and pouch to her leg with care. "Here you go, girl," he whispered, offering her a small owl treat from his pocket.

Hedwig nuzzled his hand affectionately, her feathers warm and soft against his fingers. Harry smiled, a warm feeling spreading through him at the quiet companionship they shared. "Take this to the shop in Diagon Alley, alright?" he said softly. Hedwig hooted in response, her intelligent eyes shining in the fading light.

After feeding her the treat, Harry stepped back and watched as she spread her wings silently, her form disappearing into the night sky. He lingered for a moment, watching her become a small, pale dot against the emerging stars.

—

Narcissa Malfoy sat at her vanity, absently running a silver-handled brush through her pale hair. The soft crackling of the fire was the only sound in the room, but even that did little to calm the irritation building within her. She placed the brush down, her fingers tightening slightly as she glanced at the empty corner near the hearth. Where was that blasted elf?

Dobby had been hers—well, hers and Draco's—for years now, and though he was prone to bouts of strange behavior, he was never late in responding to her calls. Yet today, for the third time, she had summoned him, and the silence had been deafening.

She rose from her seat, her silken gown whispering across the floor as she crossed to the door, her annoyance now rising into a quiet storm. She would speak to Lucius about this. It was unthinkable that a house-elf, even one as troublesome as Dobby, should ignore a direct call. No, it wasn't merely disobedience. Something was off.

Narcissa moved through the corridors of Malfoy Manor, her footsteps soft against the polished marble, but her mood sharp. As she reached Lucius' study, she found him by the fireplace, his cane resting lightly in his hand, gazing into the flames. He did not turn as she entered, but his voice, ever so smooth, greeted her.

"Narcissa. To what do I owe this visit?"

She stepped into the room, her chin tilted slightly higher than usual, her irritation barely concealed. "Dobby has gone missing."

Lucius raised an eyebrow, though he still did not turn to face her. "Gone missing?" His voice held the faintest trace of mockery. "How unfortunate. I suppose you would like me to send out a search party for the little cretin?"

Narcissa crossed her arms, her lips tightening. "I've called him three times. He hasn't come. This isn't like him, and I don't appreciate the sarcasm, Lucius. He's Draco's elf, too."

At this, Lucius did turn, his pale eyes narrowing slightly. "Dobby has always been… erratic. I'm not entirely surprised that he's misbehaving." He tapped the cane once against the floor, considering. "But I suppose ignoring a direct summons warrants more attention."

Narcissa held his gaze, her own eyes cool. "It does."

With a faint sigh, Lucius called for his personal elf. A soft crack sounded as the elf appeared at the edge of the room, bowing low until its long nose nearly touched the floor.

This elf was older, much older than Dobby—his wrinkled skin and slightly hunched posture were evidence of his years of service. His movements were measured, deeply deferential, unlike the excitable nature of Dobby. This elf had served her husband since he was a boy, a proper House Elf in every regard.

"Tivvy," Lucius said smoothly, addressing the elf, "find Dobby."

The old elf nodded, his voice soft and reverent. "At once, Master. Tivvy will look for Dobby immediately, sir." With another crack, Tivvy disappeared.

Lucius turned back to Narcissa, a faint smirk playing on his lips. "Satisfied?"

Narcissa gave him a curt nod, though her thoughts continued to turn. Dobby's absence was not something she could easily brush aside. For all his strange quirks and mutterings about 'bad wizards' lately, he had never outright disobeyed her.

"I'll wait to see what Tivvy finds," she said coolly, turning toward the door. "But Lucius… if Dobby has indeed run off, I expect it to be dealt with."

Lucius's gaze followed her as she left the room, his expression thoughtful. He said nothing, but Narcissa knew him well enough. There would be no mercy for the disobedient elf if he was found.