The Defence Professor let the door to his quarters swing shut after returning from his visits with the Weasley twins and Granger. The former visit had been far more fruitful than the latter, though the latter at least still meant an end to an annoying distraction. He regretted the necessity of what came next for the obstinate girl, but her exasperating, dangerous combination of naivety and cleverness would not allow him to protect both her and himself. If —
A sharp change in the boy's mood up above. He was suddenly very alert, and tense. The Defence Professor furrowed his brow, and willed his amazing, incredibly dangerous new device to appear before him, as he spoke: "IsolemnlyswearthatIamuptonogood." He felt a twinge of annoyance at the incantation; the act of assuming four Gryffindors' ignorant perception of "good" was distasteful, no matter how perfunctory the act or how ironic the perception.
The foolish pronouncement of the map creators' identities dissolved from the parchment. The ink quickly flitted about the page, rearranging itself to depict the first sub-level of the castle Hogwarts. At the centre of the map he saw the dot representing himself, captioned with a line of indecipherable markings; 'QUI' was legible on the left, and 'ELL' on the right, with gibberish in the middle where several names were printed over one another. He was lucky that his original name was his shortest, and his present one his longest.
He willed the parchment to zip out to arm's length, where he could see the top of the astronomy tower, and then moved it toward himself a small bit so the Ravenclaw tower came into focus. There were four dots on the tower, standing in pairs. Dumbledore and Fawkes were to the south. And to the northwest stood Harry Potter and someone Hogwarts did not know, labeled only with a question mark, next to which appeared a pawprint symbol — ah, so a magical creature Hogwarts does not know. What could —
Oh. Oh, Merlin, no.
If Dumbledore's acquiring Fawkes was a typical example, the way one acquired a phoenix was to choose to embark upon a dangerous mission where you intended to act alone against "Darkness". And the Defence Professor knew exactly what mission the boy would have in mind — he even agreed with the "Dark" assessment. The phoenix would take him to Azkaban, and Dumbledore would follow him, and the boy would cast his unique Patronus, and the Aurors would be alerted the same way they had been alerted in February, and Dumbledore would see the connection between the two events with his own eyes, and then Dumbledore would question the fool boy, who would no longer need to fear for his mentor's life —
The whole chain of events wasn't a certainty. But the one thing he could not risk in his current state was a direct confrontation with Dumbledore; it was clearly time to take precautionary measures. So the Defence Professor of Hogwarts, still Disillusioned from his walk through the castle, caught the door in mid-swing, grabbed the map and so Disillusioned it, stepped out into the corridor, levitated himself with a thought, and flew through the castle toward the entrance, all while staring at the map with barely a blink.
He tried sending an impulse to deny the phoenix, to postpone his mission, to take the safe option, but he had always failed at such attempts to influence the boy. And just as he reached the corridor to the Entrance Hall, the first part of the Defence Professor's suppositions were confirmed: Harry Potter and the new phoenix disappeared from the Ravenclaw tower, and he could feel that the boy was now many miles to the east. Within twenty seconds, Dumbledore and Fawkes disappeared as well.
At the Defence Professor's touch, the front gate unlocked and opened wide enough to admit a person, then shut and locked behind him as he flew across the grounds toward the Hogsmeade road. He felt the boy start to faint, and thought for a moment that his death might then be the best possible outcome, but not long after that he felt his recovery and subsequent surge of triumph.
He reached the start of the Hogsmeade road, which was the edge of the Hogwarts wards, willed one of the Portkeys out of his mokeskin pouch, grabbed it with one hand, and broke it with a thought. Then he sat down against the nearest tree in that unremarkable section of Norwegian forest.
The Defence Professor knew what his next move was, should he be forced to abandon his original plan; it had been calculated years ago. It was not ideal, and it would make his next few months far more difficult than they would have been, but it was accounted for, and so there was no need to plan or calculate avenues of action; he needed only to find out which ones were necessary. So he continued staring at the map, which again showed Hogwarts's first basement level.
Less than half an hour later, Dumbledore and Fawkes appeared at a corridor a good distance from his quarters. A small hesitation, and they reappeared just outside his door. Another hesitation, and they reappeared inside his bedroom. The parchment floated out to where he could see the third-year Gryffindor boys' quarters. Where Dumbledore and Fawkes then appeared.
The former Defence Professor of Hogwarts let the parchment fall to the ground and took a deep breath. Part of him, a part that was as weak as he had wanted the world to believe Lord Voldemort had been, yearned to destroy something, to unleash a burst of destructive magic, to level and burn a vast swath of forest with a thought.
But he was not that weak. He was in control. He was the master of his destiny, which was to save himself and the world from its great enemy. No one would take up his wand if he laid it down, and he, the saviour of all humanity, would not be beholden to such useless and extraneous instincts.
He thought of Harry Potter, then. A boy with limitless potential — as limitless as his own, for he had imparted it to him. A boy who could rise to defeat him, or to conquer for him. A boy he could not touch, figuratively or literally. He did not feel fondness at all, so he did not feel fondness for Harry Potter, and yet he did feel a kinship with him. The boy's mind was partly his own, and he had thought that meant Harry Potter could have grown into something like a true peer.
But that was folly after all. The boy's mind was dilute. He had spent too much time among Muggles, and would never grow to employ the proper criteria when making decisions.
And so tomorrow the world's true saviour would have to start from scratch, with a new plan and a new body. It was time to rest, to let the remnant of his host's consciousness return to the fore for a final time, and so maintain the body's life for one more day. As he started to drift away, he allowed himself one moment to partake in vain regret: Merlin damn it, I was so close.
It was a bitter, bitter voice that whispered "Mischief managed," and then the body of Quirinus Quirrell collapsed in torpor.