The silence of the white void was absolute, broken only by the soft thrum of Allen's pulse in his ears. He stared at the empty space Luna was gesturing toward, his wand tip glowing with a low, wary light.
"Luna... who exactly is Sarah?" Allen asked, his voice barely a whisper. He felt a prickle of unease. Luna lived in a world of Nargles and Wrackspurts, but this felt different. This felt like a presence.
"Sarah, could you please show yourself?" Luna asked, her voice airy and calm. "Allen is a friend. He's the one who's been looking for me."
As Luna turned her head to the right, Allen's eyes widened. A large, jagged section of hair was missing from the back of Luna's head, as if it had been shorn off by a dull blade or simply erased. The sight was jarring, a physical reminder of the trauma she'd endured while he was busy fighting his own reflection.
To any outsider, the scene was peak absurdity. Luna Lovegood was having a polite conversation with thin air. But Allen knew better than to trust appearances in a realm built of mirrors and mist. He remembered the invisible, malevolent force that had been stalking them outside the mirror—the one that had dragged Luna away. His fingers tightened around the holly wood of his wand, his knuckles turning white.
"Hi, Allen. There's really no need for all that tension. You'll give yourself a headache."
The voice was high-pitched and thin, echoing the ethereal melody he'd followed through the fog. It didn't come from a throat; it seemed to vibrate out of the very atmosphere.
Slowly, like ink swirling in clear water, a figure materialized beside Luna. It was a girl, perhaps a few years older than them, with long, cascading curls of light blonde hair that framed a face of haunting beauty. She was pale—not the healthy paleness of a girl who stayed indoors, but a translucent, marble-like white that suggested she hadn't seen a sun in centuries. Her eyes were a piercing, sorrowful blue.
"Allen, meet Sarah," Luna introduced her, her voice taking on a melodic, almost ritualistic quality. "She's the Mirror Spirit of this place. She didn't just sing to lead you here; she's the reason my soul didn't blow away in the wind."
"It was a small thing, Luna," Sarah said, her voice tinged with a profound, ancient sadness. "But I'm afraid the situation is quite dire. Your soul is safe here, but the Shadow... it has claimed your physical form. If that darkness escapes into the sunlight, I fear your world will face a winter that never ends."
"Luna's body?" Allen blurted out.
The realization hit him like a physical blow. He'd forgotten in the chaos that he was carrying a vessel. Without a word, he reached into the conceptual space of his system's pet storage. In this "Mist Dimension," the static that had jammed his interface in the mirror room had vanished. With a sharp flick of his will, Luna's physical body materialized, floating for a second before he caught it and laid it gently on the pearlescent floor.
The body looked like a doll—empty, cold, and unnervingly still.
Sarah watched Allen with a flicker of genuine curiosity, her eyes lingering on the spot where the system interface had flickered. She stepped forward, her movements fluid and silent, and gently nudged the "ghostly" Luna toward the "physical" Luna.
"Go on," Sarah whispered. "The house is empty, and the door is open."
As the two Lunas merged, a soft golden glow pulsed from the girl's chest. The Luna lying on the ground took a sudden, sharp gasp of air. Her silvery eyes snapped open, refocusing on the white void above her. She sat up slowly, rubbing her limbs as if they were cold stones she was trying to warm.
"Thank you, Allen," Luna said, her voice sounding much more grounded now that she had vocal cords again. She turned her head back to the spirit. "And thank you, Sarah. Truly."
Allen realized his manners had been lagging behind his survival instincts. He inclined his head toward the blonde spirit. "Thank you, Sarah. For everything."
Sarah's smile deepened, though it didn't quite reach her eyes. "It is a rare pleasure to meet travelers such as you. I have waited in this silence for a very, very long time. I began to think I was the only thought left in the universe."
She paced a small circle around them, her golden hair shimmering. "In truth, Allen, if you hadn't possessed the strength to shatter the Mirror Dimension and force your way into this Mist Dimension, I would have been powerless to help. I am a creature of balance, and the balance had tipped too far toward the dark."
"If it weren't for you, the Shadow would have eaten my soul like a snack," Luna added, her face uncharacteristically grim.
Allen felt the questions piling up in his mind like a landslide. "The Shadow? How did Luna even get past the mirrors? And what do you mean by 'devouring' a soul?"
"The Shadow," Sarah began, her gaze dropping to the floor, "is quite literally my own shadow. Or rather, the part of myself I couldn't bear to keep."
Allen and Luna fell silent. They could feel the weight of a story that had been waiting centuries to be told. In this realm, listening was the only currency that mattered.
"I am the Mirror Spirit created by Helga Hufflepuff," Sarah said, her voice drifting into a reverie. "When Helga passed, she left me behind to guard this sanctuary. For a long time, I was content. I had the memories of the castle and the warmth of her magic to keep me company."
She paused, her expression becoming unreadable. "But loneliness is a slow poison. Even for a spirit. I wanted to see the world, to feel the wind, but my duty bound me here. I grew desperate for a companion—anyone to talk to. So, I went into the Mirror Dimension and used the ancient glass to split myself. I thought I was creating a sister. An eternal friend."
A mournful sigh escaped her. "I was a fool. I split off all my ambition, my resentment, and my desire for the world. What stepped out of the glass wasn't a sister. It was the Shadow. She represents everything I suppressed to remain 'pure' for Helga's sake."
Sarah's voice grew ragged. "The Shadow hates this silence. She doesn't care about Helga's legacy or the 'last wish' I was entrusted to fulfill. She wants to dominate. She wants the power that lies dormant in this vault to conquer the wizarding world. For centuries, we have fought. I guarded this inner sanctum—the 'Pure Land'—while she took over the mirrors. The grey mist you wandered through? That is the battlefield where our magics have been grinding against each other for a thousand years."
"But you don't regret making her," Luna said softly, hitting the nail on the head with her usual, eerie intuition.
Sarah's eyes flickered. "No. Without her, I would have faded into nothingness long ago. She is the only thing that proves I still exist. We love each other as much as we loathe each other."
Allen's internal alarm bells were ringing. He could sense that Sarah was holding back the most critical piece of the puzzle. "If she's so powerful and ambitious, why hasn't she left? She clearly found a way to slip into the outside world—she's the one who snatched Luna from the corridor."
"She can manifest out there, yes," Sarah admitted, "but she is untethered. She is a ghost without a home. To truly leave this realm and regain a permanent, physical existence, she needs what I have here. Without Helga's heart, she is just a bad dream that will eventually wake up and vanish."
Sarah looked directly at Allen then. Her blue eyes seemed to pierce through his skull, bypassing his physical form entirely. Allen felt a jolt of shock—his Occlumency was active, his mind a fortress of hidden rooms and locked doors, yet Sarah seemed to be reading his thoughts like a children's book.
"So what is this wish?" Allen asked, trying to steer the conversation back to something actionable. "What is Helga Hufflepuff's final request?"
"My wish," Sarah said, her voice becoming firm, "is to finally fulfill Helga's command, and then to merge back with the Shadow. I want to be whole again, so that we can finally experience the world not as a spirit and a ghost, but as a complete being."
"And the wish itself?"
"Merge us," Sarah said, her golden hair shimmering with a sudden, intense light. "Help me bring the Shadow back into the fold. If you can make us one again, the secret of Helga's last wish will be yours. It is a treasure that could reshape the magical world."
Allen looked at Luna, who gave a small, solemn nod. "We have to do it, Allen. The Shadow is very unhappy. Unhappy things do mean things."
"Alright," Allen said, turning back to the spirit. "How do we find her? We can't exactly chase an invisible shadow through a mist that never ends."
"You don't need to find me, my dear Sarah... I've already found you!"
The voice didn't come from the air; it seemed to crawl up from the floor. It was Sarah's voice, but stripped of all its grace and replaced with a jagged, predatory malice.
Allen and Luna instantly snapped back-to-back, wands raised. The temperature in the white void plummeted. The pearlescent light dimmed as if a heavy curtain were being drawn over the world.
"Shadow!" Sarah cried out, taking a few eager, trembling steps forward. "Please! Look at them! With their help, we can finally do what Helga asked. We can be free! Come back to me, and let's be whole!"
"Whole?" The Shadow's voice was a shrill, mocking laugh. "Why would I want to be 'whole' with a pathetic, weeping thing like you? I don't want to fulfill the chores of a dead woman, Sarah! I am me! I am strong! I am free!"
The air began to ripple. "You sit here guarding a treasure that could make kings bow, and you want to give it away to a couple of school children? You're a bigger fool than Helga was!"
"Shadow, please..." Sarah's eyes were filled with a desperate, pleading light. "Without the merge, you're just a fading echo. You'll eventually dissipate into the void."
"Then I'll take what I need by force!" the Shadow shrieked. "I'll kill these two and leave you here to rot in your 'pure land' forever!"
Suddenly, an invisible force—massive and heavy as a battering ram—slammed into Sarah, throwing her violently to the ground.
Allen didn't wait for an invitation. He'd been tracking the ripples in the air, the slight distortion of light that even a shadow couldn't hide in a world of pure white.