In Harry's imagination, the scene of being beaten to the point of not being able to get out of bed did not occur.
After Hermione and Cedric left one after another, Harry anxiously followed William briskly through the corridor and stood before the door at the end of the hallway. As the door was pushed open, Harry at the entrance felt a blast of coldness and despair—
The feeling was eerily familiar, and Harry's thoughts almost instantly returned to yesterday afternoon, in that pitch-black train compartment, where the black-robed Dementor silently hovered above him. A force drew near, and Harry felt all his happy thoughts were slipping away.
"Snap—"
A crisp snap sounded in the boy's ear, and the sense of despair instantly ceased its spread. The boy belatedly came to his senses and realized he wasn't in the compartment of the Hogwarts Express but had already stepped into this dim room.
The next moment, Harry's gaze focused on the dark shadow floating in the center of the room.
"...Dementor?"
His Adam's apple rolled as Harry's voice trembled with horror. He stared intently at the edge of the black robe for a long time, seemingly trying to confirm if his eyes were deceiving him, "But... why has it become like this?"
Last night, driven by inexplicable curiosity, he asked Hermione about some knowledge regarding Dementors. Although she was a wizard from a Muggle background, her magic knowledge was far greater than Harry's, so he remembered things like Dementors being a non-being—a fact he kept in mind—
But now, the Dementor before him had become... unrecognizable. The originally pitch-black robe now looked more like a black miniskirt, but what floated out with the wind wasn't underwear, nor a repulsive body, but... a void.
It was as if the black robe was its main body—but Harry clearly remembered seeing that creature lift an arm, one that's putrid, ugly, soaked and decayed, and even glowing...
"Of course, it's a Dementor, the one from the train, only affected by the Patronus Charm."
William nodded and, while speaking, lowered his head to search through his pockets—only, he had a bit too many pockets, making it a big task... never mind, better leave it to the Niffler; Kabuda was more familiar with these pockets than William himself.
"But... isn't the Expecto Patronum only supposed to repel Dementors?"
Harry widened his eyes. He recalled Professor Lupin softly chanting "Expecto Patronum" to ward off a Dementor, the white mist vividly etched in his memory. Even when the white light brushed against him, a warm sensation enveloped him—
As for the white light afterward... Since it was a Nonverbal Spell, Harry never associated the blinding flash with Expecto Patronum.
"Ordinary Patrons can only repel... but mine opened up."
William nodded and then provided a completely reasonable explanation—the ancient magic he mastered had a nonsensical strengthening effect on charms, to the point he himself could barely understand it.
Safe to say, even in ancient times, not many could wield this kind of ancient magic. Had Merlin known this, the task of ruling Britain likely wouldn't have fallen to King Arthur.
"..."
"Alright, you don't need to be concerned about this now. What we need to figure out is the issue with you."
"My issue?"
Upon hearing this, Harry couldn't help but tense up, instinctively covering his heart with one hand, pretending to be calm and continuing to ask.
"Yes, ordinary spells cannot affect Dementors. Only the Patronus Charm can make these beings—non-beings feel pain. Any joyful emotion is like poison to them, so normal evil curses and curses have no effect on them."
William nodded, his gaze fixed on that floating "black cloth" in the room's center which, without doing anything, invoked an icy chill from the depths of any observing creature. His deep blue eyes slightly flickered.
"But your curse is different—just a simple 'Bone-Breaking Curse,' yet it gave this Dementor a... strange empowerment. I've researched many documents; this has never happened since the discovery from Azkaban..."
Even unsaid, William himself attempted it—from regular evil curses to curses, and finally the Unforgivable Curses. Regardless of how intensely he infused malevolence or negative emotions, the enchantments simply passed through the black cloth and vanished into nothingness.
This defies logic—the "almighty" ancient magic is rendered ineffective!
He tried to replicate Harry's scenario, even downing a vial of soul activity-enhancing Magic Potion to control variables, flames briefly sprouting from his head, yet it was all futile. Except for the Patronus, no spell had any effect on it.
Therefore, William could confidently determine that Harry possessed something he himself didn't have.
His mother's ancient magic? But he wasn't proficient in that so-called "love" emotion, despite having some experience; this could almost be ruled out. And besides that, there was the soul of "Little Tom" Harry had previously swallowed... but let's not mention that William had no clue where to find another Soul Artifact of Voldemort's, even if he did, he wouldn't just willingly implant someone else's consciousness in his own head—
All soul-related magic requires utmost caution.
Previously, while performing Fusion Magic for Harry, he thoroughly prepared, ensuring several backup plans just to protect Harry, using alternative methods only if necessary due to their potential major impact on Harry—
While assuring Dumbledore with confidence, William was practically a rookie in soul manipulation at the time.
Fortunately, everything went smoothly. Harry "consumed" the interloping soul of Little Tom, as William had envisioned, with subsequent digestion nearly perfect under William's supervision during the summer break check-up; no trace of Little Tom's consciousness within Harry persisted, meaning the digestion process had fully completed then.
So, what is still present with Harry that William doesn't know?
Crafting something blindly gets you nowhere, so William certainly didn't continue brainstorming by himself. Instead, he opted to directly pull Harry over, figuring if understanding eluded him, he might as well run a scenario simulation again.