Inside the Room of Requirement, the soft silver light radiating from Dumbledore's wand bathed Kai and Hermione in a warm, gentle glow. Their expressions were serene, almost dreamlike.
Hermione whispered, "What spell is this?"
"Expecto Patronum," Dumbledore answered, his voice calm and sonorous. "That is the incantation I'll be teaching you today."
"Does the light just calm people down?" Kai asked plainly, eyes sharp and focused.
Dumbledore's eyes twinkled. "Far from it. Expecto Patronum is one of the most advanced defensive spells in existence. It draws on the caster's most positive emotions—joy, hope, love—and forms a shield to repel the darkest of forces."
Resist darkness…
Kai narrowed his eyes at the swirling white light. His thoughts went immediately to the Obscurus bound within him. If this spell truly worked as Dumbledore claimed, it could be the key to suppressing or even cleansing the darkness festering inside him.
But this couldn't be the full spell, could it? Just a glowing shield?
"Is that all?" he asked, tone measured.
Dumbledore looked at him approvingly. "You're right to ask."
He raised his wand again, and this time the silver light surged brighter and thicker. It coalesced midair, compacting as though preparing for something unseen. Then, with a sudden wave of heatless wind, the magic burst forth into a wide luminous curtain.
Within the shimmer, a shape began to form—graceful, radiant, and alive.
A phoenix, entirely white and composed of pure light, emerged from the radiance. It soared through the air of the Room of Requirement, leaving behind trails of silvery stardust. The light it cast was pure and powerful, suffusing the space with clarity and warmth.
"A Patronus," Dumbledore said, "is the embodiment of a witch or wizard's innermost light. A guardian born of memory and spirit. Mine, as you see, takes the form of a phoenix."
The phoenix perched gently on Dumbledore's shoulder, preening its luminous feathers as though it were a living creature.
Hermione stared up at it, utterly enchanted. "Professor… can we summon a phoenix too?"
Dumbledore chuckled softly. "No, I'm afraid not. The form of your Patronus is unique to you. It reflects your soul, your subconscious—your essence. My affinity with the phoenix comes from familial bonds and long companionship. Unless someone shares a bloodline with a magical creature or has endured an experience powerful enough to imprint a magical form… Patronuses are always different."
Kai glanced sideways at Hermione. The way she was looking at the phoenix reminded him of a child longing for something just out of reach.
"Never say never," he muttered on her behalf, eliciting a soft nudge from Hermione and a small, amused smile from Dumbledore.
"Very well," the Headmaster said. "Shall we begin?"
He stepped between them, tone becoming slightly more instructive.
"To cast Expecto Patronum, you must first recall a powerful, joyful memory. Something that fills your entire being with warmth and meaning."
Kai's brow furrowed. A happy memory?
His gaze drifted to Hermione—who was already looking at him.
Their eyes met. Neither said a word, but both laughed softly, as if sharing a private joke without speaking. It was clear they had remembered the same thing.
Dumbledore smiled to himself. "Very good. Close your eyes now. Focus on that memory. Let it take root in your chest."
Kai closed his eyes.
He saw a garden in early spring, mist clinging to the ground, dew still fresh on the hedges. The window had just opened—and there she was, standing in the sunlight. A wild-haired girl in a checkered dress, practicing spells with reckless abandon, her nose scrunched up in frustration. And then she smiled.
"Now," Dumbledore said gently, "speak the incantation."
"Expecto Patronum," they echoed together.
"Good. Open your eyes."
The two complied, and Dumbledore nodded.
"Now," he said, "wands out."
Kai gestured for Hermione to go first. "Ladies before gentlemen."
She shot him a look but smiled nonetheless, her cheeks slightly pink. Her wand came up.
"Expecto Patronum!"
A pale mist of silver light appeared from the tip, but it fizzled away almost immediately.
Hermione puffed out her cheeks in frustration, but Dumbledore applauded.
"Excellent, Miss Granger. You're already ahead of most third-years. Even many adults cannot produce a visible Patronus. With more practice, I am confident you will."
The girl beamed under the praise and turned expectantly to Kai.
The boy rolled his shoulders and raised his wand.
"Expecto Patronum."
His tone was calm, almost lazy, but the response was immediate. A halo of light formed around the wand tip, then expanded outward in a curtain of pure white.
Though it wasn't as solid as Dumbledore's, the light had genuine structure and clarity. It pulsed softly, radiating warmth.
Hermione's eyes sparkled. There was no jealousy—only pride. Of course it's him, she thought.
Dumbledore, however, watched more carefully. The boy's raw talent was undeniable… but there was something else.
His brows furrowed.
Kai's mind, drifting through memory, had begun to wander. In his thoughts, the girl's golden hair shimmered in the sunlight. Her lips pursed from a failed incantation. A desire bloomed, almost painfully real.
Emotion surged. His magical output spiked.
And deep inside his body, the Obscurus stirred.
A tendril of black magic, like an eel in dark water, lashed itself to the Patronus spell. Kai didn't even notice—until it was too late.
The light curtain trembled. Then shuddered.
Kai's brow furrowed, confused. Something was wrong.
Before he could react, the light exploded.
From the burst came maggots—twisted, malformed creatures of blackness, writhing and screeching as they dove toward Kai, hungry to consume.
Hermione gasped in horror.
But Dumbledore had already moved. With a single flick of his sleeve, he summoned a radiant blast of light. The shadow-creatures sizzled, disintegrating into blackened ash.
Hermione rushed to Kai's side. "Are you alright? What happened?"
Kai looked just as shocked as she did. "I… I don't know. It was going well."
Dumbledore's face had lost its smile. He looked at Kai with calm seriousness.
"What memory were you focusing on, Kai?"