The theory had been clean from the beginning. Implementing it had been the work of three months.
The construct Kevin had built was technically a curse — there was no way around that classification. It violated the bodily sovereignty of its host without consent, established a persistent foreign magical presence, and caused ongoing physical discomfort. By the standard definition, it was a curse. Just one that had been designed to be on your side.
Like a biological immune system, it operated in phases. Dormant: barely perceptible, consuming marginally more energy than baseline, present but passive. Active: triggered by the arrival of a hostile external curse, it identified the invader, matched its structure, and consumed it. The process was deeply unpleasant — the host would feel it clearly, the way you feel a high fever rather than a low-grade one. But when the process completed, the hostile curse was gone, and the construct returned to dormancy.
In Draco's case, the existing curse was Voldemort's monitoring-and-punishment mechanism — three layers, the outermost causing pain on demand, the middle layer reporting compliance back to Voldemort, the innermost something Kevin still couldn't fully classify. Once Kevin's counter-curse was established and Voldemort next activated the existing one, his own curse would be consumed. From his perspective: he had sent the signal. Nothing had happened. His instrument had simply stopped working.
He wouldn't understand why immediately. That delay was the window.
"What if they're too elderly to maintain the increased energy intake by the time the curse runs long?" Dumbledore asked, with the precise academic interest of someone who has just identified a theoretical edge case.
"IV drip," Kevin said.
Dumbledore blinked.
"It's a Muggle medical technique. Nutrient delivery directly into the bloodstream. Madam Pomfrey could adapt it with a few charms." Kevin paused. "I'm hoping it won't come to that for a few decades."
The door hammered.
"Professor Dumbledore! Kevin!"
Dumbledore's hand moved. The door opened.
Harry stumbled through it, braced against the frame — not out of breath, but carrying the particular energy of someone who has been running on discovery rather than exertion.
"I found her. Helena — the Grey Lady — she's at Hogwarts. Ravenclaw Tower. She's been here the entire time."
A beat of quiet.
Kevin and Dumbledore looked at each other.
Dumbledore sat back. Something in his expression said he was reassembling his picture of several things simultaneously, and finding that the new arrangement was both simpler and considerably more interesting than the old one.
"The ghost has been here," he said slowly.
"Luna pointed me at her. I went to Ravenclaw Tower and she got agitated the moment I mentioned the crown — denied knowing anything, the whole thing. So I tried her name. Helena. She froze, stared at me, and disappeared."
Which meant Helena Ravenclaw, the Grey Lady, the ghost who held the Diadem's location in a secret she'd been keeping for decades, had been haunting the same castle Dumbledore administered for sixty years.
"She knows where the Diadem is," Kevin said. "And if Draco's been in the Room of Requirement looking for something—"
"He may already be close to it." Dumbledore nodded once, decisively. "Harry — go back. The Repository section of the Room. Search for the Diadem."
He conjured an image — a silver tiara, an eagle worked into the metalwork, the gem in its centre dark.
"If you find it, tell no one. Not even us until you've secured it." His eyes were serious. "If word reaches the wrong people that we've located it — that Draco's task has been completed without Voldemort's knowledge — the consequences for the Malfoys would be immediate."
Harry nodded, already moving. He understood the logic. He was out the door in under ten seconds.
Kevin turned back to the logistics at hand.
"The curse is ready," he said. "Draco, and both his parents, within the same half-day. All three."
"Lucius and Narcissa are at the Manor."
"Yes."
"Which means you need to be at the Manor while I provide Voldemort with a reason not to be."
"The cave," Kevin confirmed. "You walk in. He senses the ward breach from however far away he's sitting. He comes. I go in the back door."
Dumbledore rubbed his chin. He thought about it — not with hesitation, but with the focused, sequential quality of someone doing final verification on a plan that has already been approved.
"This is one shot, Kevin."
"I know."
"Gear up." Dumbledore's voice carried the warmth of complete confidence in someone he was trusting with something irreplaceable. "I'll send word when the window opens."
A letter appeared in the air between them — the sender's name on the front stopping Dumbledore the way almost nothing stopped Dumbledore. Kevin watched the stillness move through the old man's face, controlled in an instant.
"Anything I should know?"
"Old news," Dumbledore said. "Truly."
He put the letter in a drawer.
Kevin left him with it.
---
TY FOR COMPLETING THE GOAL OF 200 POWER STONES. NEXT BONUS CHAPTER DROP AT 300 POWER STONES.