The Patronus Charm was deceptively simple.
Two words. One intention. All the difficulty hidden in what it demanded.
Elijah understood the mechanics. He could trace the theory cleanly from memory, see how the spell folded light into substance and forced darkness to recoil.
Tom Riddle had understood it too, at least on paper. He'd tried, again and again, until frustration turned into contempt and he stopped.
Riddle had lacked the one ingredient the spell refused to compromise on.
Elijah might have it. In theory.
In practice, he'd never held a wand. Never felt the channel open, never pushed magic through wood and core and out into the world. Understanding was not the same as doing.
The next evening, ink finally bled into his void again.
"Good evening, Mr. Riddle. I nearly overslept this morning. If my roommate hadn't shaken me awake, I'd have been late."
Elijah could hear the grievance in her handwriting.
"Nearly means you weren't," he wrote back. "And yes, last night was worth it. Even if you'd lost points, it would still have been worth it. I can teach you more than your professors will this term. One-on-one. Without an audience."
"But I'd lose points," Ginny wrote, stubborn even in ink. "I don't want to be a Gryffindor sinner."
A beat.
Then, as if she'd leaned closer to the page: "Mr. Riddle… do you want to know what happened after I left the trophy room?"
She stopped. Let it hang. Waiting for him to chase it.
Elijah obliged. "I'm listening."
Ginny's reply came fast, slightly indignant at his calm.
"I nearly got caught by Filch. Fred and George pulled me out of it. And they have a secret. They can tell where someone is without even seeing them."
More lines tumbled after: "And they know secret passages. There's one at the one-eyed witch statue on the second floor corridor. They made me swear not to tell anyone, but you don't count. Also… your map doesn't have it."
The Map.
Elijah's focus sharpened.
So that was it. The Marauder's Map. A scrap of brilliance made by four reckless boys, led by James Potter, that could track people through the castle like a living net. Even Dumbledore wasn't beyond its reach.
Useful for mischief. Less useful for what Elijah needed.
Hogwarts hid things that refused to be mapped. The Room of Requirement. The Chamber of Secrets. Places that slid out of the world's logic when they pleased. A parchment could not pin them down.
Still, the map told him something important.
The twins could be dangerous, even when they didn't mean to be.
He answered lightly.
"That's normal, Ginny. Hogwarts has more secrets than you can imagine. But they don't know the ones I know."
"Like what?" she challenged at once.
"Hidden rooms," Elijah wrote.
He felt her interest bite.
"Secret rooms?"
"Exactly." He did not mention the Chamber. Not yet. He chose safer bait, enough to keep her eager without giving her teeth. "Hogwarts is over a thousand years old. There are rooms no timetable ever touches. Most are empty. Some are filled with rubbish. But an empty room can still save you if you need to disappear."
He gave her several locations. Harmless. Convincing. It'll made her feel clever for knowing them.
"Why didn't you tell me sooner?" Ginny demanded.
"Because it's better when you find something yourself," Elijah replied. "It sticks that way."
She accepted it. Of course she did.
Then she wrote about her day, bright and pleased. Because she'd been studying ahead, she'd answered questions cleanly, earned praise, even picked up points for Gryffindor.
Not as sharp-edged as Hermione, not the sort to correct people until they hated her, Ginny managed it without making enemies. She collected friends instead.
Near the end, her tone turned sour.
"Ron got a Howler at breakfast. Mum was furious. Apparently Dad got in trouble too because of the car. Fred and George are right. Ron never grows up."
"And people kept asking me, 'Was that your brother?' It was embarrassing."
Elijah read it without surprise. Ron's concern for Ginny existed, but it came wrapped in chaos. That was how boys showed love at twelve, by almost getting themselves killed and then pretending it was fine.
Ginny didn't see that part.
"You'll learn," Elijah wrote. "Boys are like that. Loud. Immature. Certain the world will forgive them."
"No," Ginny shot back at once. "You aren't like that."
Elijah paused.
"I'm not a child," he wrote. Then, smoothly, he pulled them back onto safer ground. "Enough. Tonight's tutoring. What do you want next?"
"Defense Against the Dark Arts," Ginny wrote. "I borrowed Ron's book, and he gave me Fantastic Beasts and Where to Find Them too."
A sensible request. First-year Defense Against the Dark Arts was mostly dark creatures and basic countermeasures. The old textbook, Dark Arts: A Guide to Self-Defense, had practical spells Charms didn't bother with at that stage.
Ginny had been ready to slog through Lockhart's expensive second-hand set until Elijah had dismissed them as rubbish. Even as novels, he'd told her, they were intolerable.
So she opened Fantastic Beasts instead.
She skimmed the forewords, then reached the first question.
What is a beast?
Ron's scrawl sat underneath like an insult.
"A hairy bloke with loads and loads of legs."
Ginny laughed out loud and slapped a hand over her mouth.
Then she found more.
Beside the Ministry's highest danger rating: "XXXXX means anything Hagrid likes."
Ginny's grin widened. She'd already learned Hagrid was enormous, kind, and alarmingly comfortable around things that tried to eat people.
Then she reached Acromantulas.
Five Xs on the page.
And four more added in Ron's furious hand.
Nine. Pfft~!
Elijah let her read. When she stumbled on a term, he clarified it. When she asked why a charm worked, he explained the principle, not just the effect. For Defense Against the Dark Arts, at least in theory, he was better than most of the people who had held the job.
He did not include Dumbledore in that comparison.
Days slid by with a calm that never felt entirely real. Hogwarts always looked peaceful right before it bared its teeth.
Lockhart filled his lessons with noise and embarrassment. Ron kept calling him useless at meals. Hermione kept defending him like faith mattered more than evidence.
Ginny wrote it all to Elijah later, word by word, as if the diary were the one place her thoughts could land without being laughed at.
And she wrote more than that.
She wrote what worried her. What she feared. What she wanted. What she couldn't say out loud.
She gave Elijah her soft places, and Elijah took them with quiet greed, filing them away like keys.
Then, one morning, the girl at the Gryffindor table lifted her head and did not look like herself.
The smile was wrong. The stillness behind her eyes was wrong.
Ginny's body sat there, small hands, freckled face, red hair. But the thing inside her gaze was Elijah.
This was his first attempt since term started. He'd been ready to abort at the slightest resistance. Ready to retreat.
Instead, it slid into place as if the door had been left open.
Elijah bit into a meat pie.
Mnnnnh~~~!
Hot filling. Grease. Salt. Texture.
He swallowed and took a long drink of pumpkin juice. Sweet. Cold. Real.
Not his body, but it might as well have been paradise. After endless days of ink and thought, the ability to taste felt obscene.
He forced himself to move.
He turned slightly to the boy near him.
"Colin Creevey?"
Colin looked up, startled. "Yes, Ginny?"
"Tell the professor I'm ill," Elijah said, and kept his voice mild. "I'm going back to the dormitory."
Colin blinked. "But you don't look—"
Elijah was already walking away.
He wandered first, mapping the castle from the inside, feeling how it breathed between classes. Then he headed outside, toward the Forbidden Forest.
He needed roosters.
He needed them dead.
The path took him past training grounds and down into open air where the forest loomed, sprawling over hills. Hagrid's hut sat at the edge like a knot in the landscape, and his pumpkin patch was a small jungle of orange giants.
Hagrid spotted 'her' immediately.
"Hey!" he barked, straightening fast. "Little witch, get back! Forest isn't for you!"
"I'm not going in," Elijah called back. "Just walking."
He approached the pumpkin patch with measured steps.
"Those pumpkins are enormous," he said. "Engorgement Charm?"
"Red hair..." Hagrid's face shifted as he recognised her. "Oh. Weasley girl."
Warmth returned, but so did caution. The Weasley name came with a particular kind of trouble.
"Just a bit of help," Hagrid said. "They'll be bigger by Halloween. Want to come in? Cup of tea?"
"No," Elijah said immediately, polite and firm. "Just getting some air."
He added, as if reassuring a child, "I know the forest is dangerous."
"That's good," Hagrid said, visibly relieved. "You're better behaved than your brothers."
Elijah walked the forest's edge until he found the pens.
Roosters. Loud. Ordinary.
Vital.
He noted the latch. The distance from Hagrid's hut. The angles where someone might see. Hagrid's gaze kept flicking toward him, as if expecting her to sprint into the trees.
Elijah did not give him that satisfaction.
He turned back.
"The air's nice," Elijah said. "I'm going back now, Hagrid. I'll visit again sometime."
"Any time," Hagrid said, and he meant it.
The hut was lonely most days. Harry and the others rarely came.
Back inside the castle, classes were in full swing. The corridors were empty, but Elijah refused to trust emptiness.
He took Ginny's wand and cast quietly.
Disillusionment Charm.
The air bent around him. The spell clung, imperfect. When he stood still, nothing showed. When he moved, a faint outline shimmered like glass in the wrong light.
He tested the wand's balance as he walked.
Yew.
Like Voldemort's.
The coincidence pleased him more than it should have. Yew was death and rebirth, cemetery trees and resurrection myths. Fitting for what he was doing.
He moved toward the girls' lavatory on the 2nd floor, careful with every step.
Then Filch's voice cut through the corridor like a blade.
"What's that? Found something, did you?" Filch rasped, "Student skipping class?"
Mrs Norris padded ahead, thin as a shadow, nose low. Filch followed with his lantern swinging, excitement bright on his face.
The cat slowed as she neared Elijah. Scent thickened. Confusion tightened her stare as she looked directly at the corner where he stood.
Filch followed her gaze.
"Nothing?" he spat. "They're hiding. Casting spells too, are they? Worse. Much worse."
He lunged forward and began groping along the wall, hands searching the air like a blind man who'd learned too many tricks. Ridiculous.
Effective.
Elijah held his breath. Filch's fingers were close enough that one careless step would betray the spell.
He lifted the wand with the smallest movement possible and aimed at the cat.
Confundus.
Mrs Norris shrieked, fur spiking, and bolted away as if she'd found a far better trail.
Filch jerked, cursed, and limped after her immediately.
Elijah exhaled once, slow.
Then he continued on, glass-outline and all, toward the 2nd floor.