"Good evening, Mr. Sorting Hat."
Listening to that listless voice, William greeted cheerfully.
Who told you to want to sort me into Ravenclaw—not the one getting lost climbing stairs in the castle.
"Kid, this is serious—" the Sorting Hat's voice became a bit deep, but it seemed to get more and more indignant, "You actually dared to cast a spell on the great, fearless, wise, and brave hat of Gryffindor, this is simply... outrageous!"
Half of those weren't even your adjectives, were they?
"Mr. Hat, I don't think Professor Dumbledore would necessarily believe an accusation made by a patched, and even adjective-less hat against a brilliant Hogwarts student."
William said sincerely, though only in his mind, since Snape was still staring at him intensely from behind—though he didn't step forward to stop him, maybe he was waiting for Dumbledore to come back so he could show the old man just how... unruly William was.
"Brilliant student?"
The Sorting Hat loudly repeated, as if William had just told a huge joke.
"Oh, come on, kid, I remember clearly!" it continued, "You ended the Goblin Rebellion, defeated the Black Wizard Clan, stopped poachers from harming magical creatures in the Forbidden Forest, won the battle to defend Hogwarts, and even..." the Sorting Hat's voice grew quieter.
"I'm listening?" reminded William, who hadn't heard enough.
"But... but you actually do seem to be a good student..." the Sorting Hat mumbled, a bit confused.
"Now you understand?" William smiled; the effect of the charm clearly hadn't worn off, this hat had muddled itself up, none of the mentioned achievements had anything to do with the word "student."
"...But that doesn't justify you cursing me!" the Sorting Hat quickly shook its brim and said angrily.
"I apologize to you, the great, fearless, wise, and brave hat of Gryffindor," William said sincerely.
"That's... that's better." The hat was momentarily stunned, muttering as it softened, then curiously asked, "So how did you do it—I mean, show up after a hundred years? And you're so... small."
The hat picked an adjective, although not quite fitting.
In the wizarding world, people over a hundred years old are not uncommon—but William's situation was indeed unprecedented for it.
At least the Sorting Hat hadn't heard of it.
"I'm puzzled too, I almost became Dumbledore's teacher—" William shook his head, not minding sharing this with the hat, after all, this hat is a legitimate "old thing," what if it had come across something similar?
"But, Hat, I have a reason to stay at Hogwarts—"
"...Related to the thing underground at Hogwarts, right?"
Half and half—though William certainly didn't say that, he just nodded solemnly.
"...Alright, I promise you, I suppose I won't tell Dumbledore," the Sorting Hat muttered, agreeing with William.
At that moment, the office door was pushed open from the outside, and Dumbledore walked in, dressed in a moon-white robe, with a crooked maroon hat atop his head, and a silver-white beard draping to his waist,
but the most attention-grabbing thing about the old man wasn't his attire, nor his crooked nose, but his shoulder. On Dumbledore's shoulder stood a rather unusual-looking bird.
...Phoenix?
Looking at the ugly bird with remnants of golden-red feathers, William quickly recalled this magical creature.
"Fawkes is about to enter her Nirvana, I thought I'd take her out for some fresh air—by the way, she's a Phoenix," the old man placed the Phoenix on the stand behind the door, turned to look at the top of William's head, "It seems you and the Sorting Hat are getting along well?"
"Of course, Professor Dumbledore—"
William nodded, taking off the Sorting Hat from his head and placing it back on the stand. The hat lightly twisted its body, and its brim flopped down softly.
"Sit down, William... oh, please allow me to call you that." Dumbledore sat in the high-backed chair behind the desk. Then he waved his hand, and two nearby stools on the bookshelf suddenly lifted their legs and hurriedly ran to the middle of the office.
William followed suit and sat down, while Snape remained motionless, still leaning against the wall.
"I apologize for calling you here so late, William, Professor Snape is curious about some of your actions and suggested talking to you face-to-face..." Dumbledore sighed, showing a helpless expression on his face.
"It's an accusation, Professor—" dissatisfied with Dumbledore's rather gentle wording, Snape stepped forward a few steps, taking over the conversation as he stared intensely, "the spells you cast earlier tonight on the Black Lake..." he leaned forward, staring hard into William's eyes, "I have not taught you these, and this is absolutely not the ability a newcomer who just entered the world of magic after living in the Muggle world should possess!"
Even many sixth-year students cannot master these spells proficiently—
Of course, Snape didn't say the latter half of the sentence because that seemed to admit Hogwarts' education level was lousy.
"—didn't teach me?" William chuckled, "So is Professor Snape now admitting that he wasn't serious enough about guiding my pre-school education during summer break, neglecting his duty for the Ministry of Magic?" William emphasized the latter part of the sentence.
Never fall into the trap of self-validation.
As for why Snape would be so clearly aware of the situation on the lake surface—William calmly met Snape's gaze and guessed the answer.
Just like at the bookstore entrance in Diagon Alley, Snape is definitely a powerful Legilimens. And half an hour ago, he was with the two students on the train for a long time—obviously, either Harry or Ron had seen William's spellcasting process clearly.
Snape was obviously stuck by William's question, and he even forgot to specify the details of the "accusation"—although these spells are not within the scope of "pre-school education," in the Ministry of Magic's task, the accompanying professor is responsible for teaching and also for safely bringing transfer students to Hogwarts Castle. For some reason, he only threw William a schedule of the Hogwarts Express.
He indeed "neglected his duty."
"I..."
"I think perhaps Professor Snape was delayed by something important—" Dumbledore suddenly spoke up to bail Snape out, bringing the topic back, "I think, maybe you could also answer Severus's question?"
William turned his head, locking eyes with Dumbledore, but without the slightest panic, nodded, "Although Professor Snape didn't fulfill his duty." He emphasized again, Snape's face turned greener, "Because of my curiosity for magic, I frequently went to Diagon Alley during the last half of my summer break."
This is true; he indeed frequented Diagon Alley.
"And perhaps because I have some talent in magic, I quickly mastered many spells from the Charm Books—"
This is also true; he learns charms like finding extra points in deep blue.
"Most of these spells were self-taught from Charm Books, except for the Levitating Spell—" He looked up at Snape, "which was taught by a professor." He didn't specify which professor, so this part was true too.
"That's impossible, huh, talent—" Clearly, Snape scoffed at William's explanation.
"Are you jealous of me because you lack talent, neglectful professor?" William took advantage of the situation to emphasize and repeat the question, once again stumping Snape.
"I..."
"Alright, Severus, that's enough." Dumbledore interrupted Snape's rebuttal, shaking his head, his silver beard slightly quivering, "William has already given his answer, I think your doubts should have been resolved."
"But, Dumbledore, you promised—"
"Enough, Severus. I believe William has no issues."
Dumbledore repeated, his firm stance surprised William a bit, as he expected Dumbledore would continue to side with the professor, which was reasonable, just like the former Headmaster Blake.
He even prepared for what to say next, but now it seems this headmaster knows what's what—
Thinking this, William glanced at the painting frame beside him with Headmaster Blake who always kept his eyes closed.
Alas, comparing goods is indeed unsatisfactory.
However, it's normal for him to be suspected; a Muggle-born little wizard who's lived in the Muggle World until 15 without touching the Magic World but can cast some very advanced spells is indeed strange—
Of course, the key point is, Professor Snape seems very concerned about his hair.
And William... "attacked" his hair at the first meeting.
"Sorry about tonight, William," Dumbledore said, "Professor Snape will safely escort you back to the Hufflepuff common room, I presume I'm right, Severus—"
"Hmm..."
After a long silence, Snape reluctantly grunted.
"Today is your first day at Hogwarts, I wish you a wonderful evening."
The elder responded with a playful wink of his pale blue eyes to William.
...This old man's eyes are definitely faulty, William followed Snape out of the Headmaster's Office and nodded with certainty.