The castle breathed.
Stone exhaled a damp chill that crept beneath Elara's coat and laid cold fingers along her spine. Torches hissed, somewhere far down the corridor water dripped, steady as a metronome in the dark. She had sworn never to come back… not to this castle, and not to him.
At the door with its black iron sigils she stopped. The wards were old, layered and sharp. Someone had reforged them recently, not with finesse but with anger. Typical.
Elara pressed her palm to the wood. The sigils pricked at her skin, curious. A pulse of her own magic met them, calm, deliberate. The door considered her, then softened by a fraction.
"Do not touch that."
The voice came from the other side, rough and unmistakable. The door unlatched. He stood there, tall, dark, eyes like polished coal. He looked like a man who had been dead and chosen spite over peace.
"Severus," she said. The name burned in her throat.
"You," he answered. His gaze travelled down her coat, her gloves, the case at her hip. "They sent you."
"The Ministry insisted."
"I told them I work alone."
"And I told them I do not take orders."
His mouth tilted, not in amusement. "Spare me the performance of reason."
"Yes," she said, "I came anyway."
He turned his back and walked into the laboratory. It was both a dismissal and an invitation. She followed, because she always had, even when she hated herself for it.
The room bore his signature, precise, restrained. Glassware ranked like soldiers, benches stripped of clutter. One lamp burned over a matrix of runes carved into slate, casting yellow light across ink-stained notes. The rest of the torches flickered green along the walls, sickly and beautiful.
"You should not be here," he said.
"We are past that line." She placed her case on a bench and pulled off her gloves. "Say it if it comforts you."
He turned. The years had carved his face deeper, but the expression was the same, measured contempt hiding something less certain. The same restraint that had once drawn her closer.
"You always mistook persistence for courage," he said.
"And you always mistook grief for virtue." Her tone was too even. "We are both still tedious."
A nerve moved in his jaw. The silence between them felt alive.
She looked past him to the slate. "You mapped the bleed lines."
"Of course."
She stepped closer. The pattern was wrong, deliberate misalignment, a whisper of compulsion disguised as purification. Whoever had written it wanted the castle to feed on itself.
"This isn't residue," she said. "Someone primed it to react."
"I know," he replied simply. "The castle amplifies conflict."
"Then you invited me into it."
"I did not invite you anywhere. The Ministry forced it."
"Convenient." She touched the edge of the slate. The stone pulsed once, bright. The lamp flickered.
He stepped nearer. "Do not feed it."
"Do not tell me how to feel."
He stopped within arm's reach, heat seemed to travel the short distance between them. She hated that her pulse noticed.
"You think I didn't see you in Hogwarts," she said. "When I came back. When I was old enough to make my own mistakes. You made a religion of a woman you'd already buried."
His face stayed still, but the air thickened. "You presume to audit my dead."
"And you presume they absolve your living." She drew a breath. "We both know what we are."
"Remind me."
"Efficient at triage, miserable at mercy."
He gave a sound that might have been a laugh. "The castle is not a patient. It's a wound that thinks it's a body."
"Everything with a memory does." She took out a copper rod and a small vial of reagent. "We'll need resonance, not force. Whoever set this loop wanted to harvest conflict."
He glanced at the vial, then back at her. "From what source?"
"Us," she said. "The people who work in it. The argument. The desire."
He went very still. She moved to the cracked wall, placed the copper against the stone, and hummed softly, a tone that matched the castle's heartbeat. The wall sighed.
"You still hum when you work," he murmured.
"You still listen when you shouldn't."
He came to her side. The heat of him reached her before his words did.
"Tell me your plan," he said.
"Disrupt the loop, re-route the bleed lines, starve the compulsion." She touched the vial to the seam. "If it clouds, we stop."
"And if it doesn't?"
"Then you follow my lead."
He hesitated, then nodded once.
The glass cooled, then shivered. Clear. She pushed a little more magic through the copper. The torches leaned green, air tightened.
"Enough," he said quietly.
"Not yet."
A tremor shuddered through the walls. The slate runes lit in a sudden circle of light. The wards on the door flared and sealed. Shelves rattled, one bottle slipped, shattered.
Elara felt the pull inside her chest, the spell seeking heat, anger, desire. She fought it with discipline, but purpose turned into pressure.
Snape's hand caught her wrist. The shock of contact burned through the restraint. The reagent flashed grey, then cleared. The copper hissed with heat. She did not let go.
He was close enough that she caught the scent beneath the dust and potions, clean, dark, rain over stone. It made her throat tighten. She turned her head slightly, his mouth was a measured line, all control.
"Release me," she said, low.
"Do not feed it," he murmured. "It wants what you're holding."
"And what am I holding?"
"Conflict," he said. "And too much of it."
Her breath hitched, but she held her ground.
Elara slid the copper rod between their wrists and pressed its tip to the slate. The runes hissed, the light faltered. She steadied the hum in her throat until the air cooled. His grip adjusted, not harsh, simply there, solid. It shouldn't have helped. It did.
The slate cracked softly, the torches steadied to orange. Stone exhaled.
Only then did she realise her hand still rested against his forearm. She withdrew it slowly, unwilling to name the pause.
"This was tampered with," she said. "Someone wanted us to trigger it."
He exhaled once. "It's not the first alteration."
"Then there will be more."
He studied her face. "You resent me."
"Sometimes."
"For what?"
"For making me speak to a shrine when I wanted a man," she said. "For choosing ghosts when the living stood in front of you."
He absorbed it, unmoving.
"We can't do this if you're going to catalogue my sins," he said softly.
"And we can't if you pretend you don't feel anything."
A groan rolled through the wall behind them. The torches snapped once, bright then dim.
"Do you feel that?" she asked.
"Yes," he said.
A bench scraped, runes flickered like veins under skin. She reached for the rod. Glass chimed.
"Down," he said.
Light. Heat. Noise.
The wall spat fire.
He moved first, arm over her shoulders, body between her and the blast. The wards caught most of it, but the impact tore through the air, ripping dust and shards across the room.
The lamp blew out. The torches guttered to green, then black.
He pushed her beneath the bench, shielding her. Her lungs stung with smoke, her heartbeat clashed with his. Somewhere above, a bottle rolled and cracked. Sparks hissed and died.
She pressed her palm to his chest, to steady herself, maybe him. The contact anchored them for a heartbeat that felt too long.
Then the wards began to scream.