Hermione Granger did not have an easy Christmas holiday.
It wasn't that Christmas at the Grangers' lacked warmth.
Quite the opposite. There was perfectly roasted meat, a table her mother had set with care, holiday decorations her father had hung crookedly and her mother had complained about, and a Christmas tree in the living room that, while no match for Hogwarts', was lovely in its own right.
The problem was that Hermione couldn't stop thinking.
And once Miss Granger had something on her mind, she found it hard to give herself a real break.
Especially when the person responsible was named Gavin Gu.
More precisely, it was the books Gavin had been looking up lately, his strange state, and the calm way he had questioned and refused her outside the library.
She couldn't put it out of her mind.
To be honest, those last words had hurt.
So only two days into the Christmas holidays, she pestered her father into taking her to a bookshop that was still open.
"Psychology?" Mr. Granger looked distinctly surprised as he pulled a book from the shelf. "Have they started teaching that at Hogwarts?"
"No," Hermione said quickly. "But I think I ought to read up on it. Broaden my knowledge."
She didn't explain further.
Even if she did, her parents would probably have trouble understanding why their eleven-year-old daughter was trying to use Muggle psychology to work out what dangerous experiment another eleven-year-old wizard might be conducting.
It didn't sound particularly conducive to the Christmas spirit, either.
In the end, Mr. Granger bought her several books.
Introduction to Psychology, Psychology and Life, Trauma and Recovery, Basics of Hypnosis, and The Mind and the Subconscious.
They were among the more basic, practical psychology textbooks they could find. None was too thick, at least compared with the books at Hogwarts.
Hermione still remembered Gavin's borrowing record, but some of the books were impossible to find, so she had to substitute similar ones.
She felt fairly confident carrying them home. She had always placed great faith in books. As long as the words were clear and the logic held up, she could work her way through them.
Then she opened the first book and read twenty pages.
She understood seventy percent of the words.
But only thirty percent of what they meant.
Hermione stared for a long time at a page discussing "defense mechanisms," "personality structure," and "post-traumatic repression." For the first time, a nonmagical textbook felt like hard going.
"...That doesn't make sense," she muttered, beginning to doubt herself.
But she didn't give up.
When she didn't understand something, she underlined it, noted down the terms, and went back to reread it. She worked forward one concept at a time. It was much slower than usual, slow enough to frustrate her, but she gritted her teeth and kept reading bit by bit.
She didn't even know why she was doing it.
Maybe she wanted to prove something.
Or maybe she was simply angry.
As for Christmas presents—
Hermione froze for a moment when she unwrapped the sweater Gavin had sent her.
Blue.
A deep, unmistakable blue.
She couldn't understand why a yellow-clad Hufflepuff would give a Gryffindor like her a sweater in something so close to Ravenclaw colors.
The wool was good quality, and the stitches were fine. It clearly wasn't a thoughtless gift. At first, she only thought the color looked familiar. Then her mother came over, glanced at it, and said with a smile:
"That's a lovely Oxford blue. Who sent it?"
Only then did Hermione look down carefully.
Sure enough, it wasn't just the color. A tiny crest had been discreetly embroidered on the chest.
Oxford's crest.
Her finger rested on the little crest for a moment. She said nothing.
When she was younger, she really had dreamed of schools like that.
In the book of her memories, Oxford had always seemed enchanting: ancient colleges, imposing libraries, professors devoted to their fields, walls steeped in history, and people clever enough to understand one another. Later, when her letter from Hogwarts arrived, those dreams had naturally taken another direction. But that didn't mean she had never longed to go there.
Almost at once, she understood what Gavin meant by giving her the sweater. He thought she belonged there.
That left her with mixed feelings.
It wasn't as though he had won her over on the spot.
She still wasn't ready to forgive Gavin for saying she "couldn't help right now." The words had stung, even if they were probably true.
But she put the sweater away carefully.
When she packed her Suitcase, she hesitated, then folded it with care and placed it at the very bottom.
She planned to take it to Hogwarts and wear it if the occasion arose.
Only if the occasion arose, of course.
It certainly wasn't because she actually liked it.
Hermione returned the day before the holiday ended, earlier than most students.
She had never liked leaving things until the last minute. Besides, going from her Muggle home back to Hogwarts took a little time to adjust to. She needed to get her mind out of Muggle World mode and back into wizarding mode.
But as soon as she entered the Great Hall for lunch, something felt off.
She looked around and realized that the familiar figure eating elegantly with chopsticks was missing from the Hufflepuff table.
Gavin didn't seem to be there.
Something was clearly amiss at the Hufflepuff table, too. Justin was talking to someone with the expression of a person who had already explained himself far too many times. Ernie looked more solemn than usual, like a press secretary working hard to keep public opinion in the house under control.
Hermione had barely sat down when she picked up the news from the chatter around her.
Not the full story.
Rumors.
A great many rumors.
And they were rumors of the sort Hogwarts specialized in—the kind that grew steadily more absurd after several rounds of retelling.
"I heard he caught a Wild Dragon on the Astronomy Tower. You know, a Hungarian Horntail?"
"Nonsense. He just happened to be there when a dragon egg hatched."
"No, he was practicing some dangerous advanced magic. I heard it was Fiendfyre. That's why there were scorch marks."
"My cousin in Gryffindor said he heard the Astronomy Tower get hit by a magical cannon this morning. By the time he got up, half the tower was gone."
"Someone even said he summoned an army of ghosts to attack Hogwarts, but his spell went wrong and the army descended on the Astronomy Tower instead."
"That's ridiculous."
"That's exactly what happened. I saw it with my own eyes." The speaker sounded so certain that you'd think he had been there—a pillar of the Astronomy Tower, watching the whole thing unfold.
More than a dozen versions flew around the Great Hall.
Hermione sat eating, but the food tasted like nothing. The more she heard, the more her stomach churned.
To everyone else, it was simply the first hot topic at Hogwarts after the holidays.
But she knew it wasn't that simple.
When Gavin refused to let her help, she had thought he was just being unbearably arrogant. Now, hearing rumors of the Astronomy Tower, experiments, explosions, and injuries, she realized for the first time:
So this was why you wouldn't let me help?
It wasn't simply that he looked down on her.
It was that the whole thing really was that dangerous.
So dangerous that he hadn't even intended to let her near it.
Hermione's grip on her fork tightened slightly.
Her imagination ran away with her, inventing an entire account of Gavin's painstaking intentions: researching alone, preparing alone, keeping every danger in his own hands, and finally refusing anyone's help because that would drag them into the mire with him.
As she thought about it, some of her resentment toward Gavin seemed to fade.
Admittedly, the whole drama she had imagined felt plausible.
But if Gavin knew about it, he might have twitched his lips and wondered whether that was really what he had been thinking at the time.
Just then, another commotion broke out at the far end of the Great Hall.
Hermione looked up and saw Cedric hurrying in from the Entrance Hall. He had clearly only just returned to school. He looked agitated, and almost before his left foot had crossed the threshold, he was scanning the room as though searching for someone.
"Who's he looking for?" someone nearby asked.
"Gu, probably."
"What does he want with Gu?"
"No idea."
Cedric had plainly heard some of that, but he had no time to respond. His gaze swept along the Hufflepuff table. When he didn't find Gavin, he grew even more anxious. People asked what was wrong, but he refused to say a word beyond "Nothing" and "I'll tell you later." His face, meanwhile, had gone bright red.
Oddly, it wasn't entirely the flush of worry.
It looked a little more like—
He was delighted, but barely able to contain himself.
As though he was carrying an enormous secret he wanted to show off, while someone had tied his mouth shut.
Watching him only made Hermione's feelings more complicated.
Cedric was hardly the sort of person who usually looked so strangely caught between smiling and fretting.
And the person responsible for all of it clearly hadn't returned yet.
By the time Gavin came back from St. Mungo's, it was already the second day of term.
The past few days had been—
Complicated.
On one side, there was Cordelia's unprecedented tenderness as she cared for him—
Accompanied, of course, by close surveillance and the ever-present threat that she would "donate herself to the Department of Mysteries if he dared experiment on himself again."
On the other side was his research into the Obscurus. He had finally made fresh progress, only to be stopped by a force he couldn't resist. Trying to suppress his curiosity again left him with a persistent, maddening itch to get back to it.
Heaven and hell, side by side.
And he kept moving between them.
Sometimes Cordelia would sit by his bed and read letters to him in a soft voice while Dibby brought him warm milk, and he would feel that a few more days there might not be so bad.
But the next moment, Cordelia would glance at him as if to warn him not to entertain any ideas he shouldn't, and he would be sharply reminded:
This is house arrest.
With emotional blackmail thrown in.
Still, he had to return to Hogwarts eventually.
Before he could decide whether the place was heaven or hell, the day of his discharge arrived.
Before he left, Cordelia stood by the hospital room door and straightened his scarf. Then she made a gesture that was unmistakably threatening.
Its meaning was clear:
Don't forget what I told you.
Gavin nodded.
"Understood."
Then he immediately started thinking, Once I'm back at school, I can finally continue my research.
He would have to be careful this time, of course. He had promised Cordelia, and he couldn't put himself back in St. Mungo's.
Just thinking about Cordelia's threat still frightened him a little.
This time, Gavin returned to Hogwarts by Fireplace.
It was a discreet entrance.
At least, that was the plan.
The green flames had barely died when Gavin stepped out of the small Fireplace in the Headmaster's Office. Before he could brush the ash off his robes, Professor McGonagall caught him.
"Mr. Gu." Professor McGonagall stood there, stern and unsmiling. "Before you go to the Great Hall, I believe we need to establish one thing."
Gavin straightened at once.
"Professor."
"For the entire coming term, you are not to ask for leave or leave a professor's sight. I mean during every single class."
"What? Professor, but..." Gavin had been about to protest, but the dangerous look in McGonagall's eyes persuaded him to close his mouth.
"I do not care for 'but,'" Professor McGonagall said sharply. "And you are not to do anything unrelated to your lessons, at any time or in any place."
"Yes, Professor." Gavin nodded, trying to look as obedient as possible.
"Good," Professor McGonagall added. "We'll discuss the rest after you've seen Dumbledore."
Gavin sighed inwardly.
"Understood, Professor."
"Off you go, then. And remember to attend your classes." Professor McGonagall did not look at him again.
After that lecture, Gavin's steps slowed a little as he entered the Great Hall.
He had thought he was being discreet enough.
But clearly, he had underestimated how quickly Hogwarts students spotted a rare creature.
His right foot had barely crossed the threshold when a sharp-eyed Hufflepuff saw him.
"Gu's back—!"
That shout worked wonders.
The next second, at least half the Great Hall looked up at once. The Hufflepuffs and Gryffindors reacted especially quickly, like two hunting parties who had just learned that a legendary creature had reappeared on the map.
"Gavin's back!"
"He really is back!"
"I told you he was still alive!"
"That's not a very lucky thing to say, is it?"
"That doesn't matter. What matters is, he's back!"
Applause broke out first at the Hufflepuff table, and Gryffindor joined in with cheers. Even a few Ravenclaws looked up, wearing expressions caught somewhere between curiosity and disdain.
Gavin had barely taken two steps when the twins rushed him from either side.
"He's back!"
"Our hero!"
"The king of Hogwarts has returned!"
"The king has finally returned to his loyal domain!"
Before Gavin could voice a single objection, they each grabbed an arm and hoisted him up.
Literally hoisted him.
Like they were carrying a sedan chair.
Gavin's feet were half an inch off the floor.
"Wait—"
"One lap around the hall!"
"A tribute to the great Tower Conqueror!"
"And the legend who nearly got all our classes canceled on the first day back!"
The Great Hall erupted in laughter.
Harry and Ron were nearly doubled over onto the table. Even Hermione couldn't keep a straight face; the corner of her mouth visibly twitched. At the Hufflepuff table, some students banged on the table while others cheered. For a return to school after a serious injury, the whole scene was remarkably unlike what anyone might have expected.
It felt more like a lively house celebration.
"Put me down," Gavin said helplessly.
"A king can't walk on his own."
"It would be beneath his dignity."
"Besides, look. Everyone's in favor."
Gavin looked up and found that quite a few people were indeed still applauding.
"...Your welcome could use some work."
The twins clearly had no intention of working on it.
They really did carry him all the way around the Great Hall. They were about to start a second lap when Professor McGonagall appeared in the doorway and fixed them with a deadly stare. Reluctantly, they set Gavin down.
The moment his feet touched the floor, people crowded around him.
"What did you actually do?"
"Did you really blow up the Astronomy Tower?"
"Were you fighting the Wild Dragon that attacked Hogwarts?"
"Someone said you caught a dragon, someone said you were studying Dark Magic, and someone else said an angel descended upon you—"
"Stop." Gavin raised a hand. "One at a time."
Unfortunately, Hogwarts had never been good at one at a time.
In the end, Gavin could only give the "official account" Professor McGonagall had provided him:
"I was testing some magic, and something went wrong."
Everyone stared at him.
Their expressions were remarkably alike.
Do we look like we believe that?
"That's it?" Ron asked.
"That's it," Gavin said.
"So there really wasn't a Wild Dragon?"
"No."
"Or an ancient evil artifact that went out of control?"
"No."
"Then why did you blow up half a tower?"
"I told you. It was an accident."
Harry looked at him, then at the people around them, who plainly preferred the dragon-fight story. At last, he said with complete sincerity:
"I think everyone else's version is more convincing than yours."
Gavin fell silent for a moment.
"Then pick whichever one you like."
That answer clearly didn't give his audience the heroic story they wanted. They went back to talking over one another, offering their own theories, until the laughter and noise gradually settled. It was still dinnertime, after all. However curious they were, they weren't going to keep him surrounded until the meal was over. After a little more skeptical questioning, the crowd finally dispersed.
Once there was room to move, Cedric seized his chance to squeeze through.
He wore a mysterious expression and kept his voice low, though his eyes shone with excitement.
"Gu."
"Mm?"
"Your Christmas present was far too expensive."
Gavin glanced at him.
"If you don't want it, give it back," he said irritably. "I'm deep in debt now."
Money was the last thing he wanted to hear about. Just thinking of it made his heart bleed.
Cedric immediately took half a step back, as if afraid someone might actually take the gift from him.
"Not a chance," he said quickly.
"Then why bring it up?"
Cedric glanced left and right and lowered his voice further, looking thoroughly secretive.
"I just think we've got Gryffindor beaten."
Gavin raised an eyebrow but said nothing.
A few Hufflepuff students nearby, who hadn't quite wandered off, looked equally baffled.
"What do you mean, beaten?" someone asked.
"What are you talking about?"
"Cedric, did you secretly drink something you shouldn't have over Christmas?"
Cedric pressed his lips firmly together. He had evidently weighed "thank him for the gift" against "never reveal what the gift is" and chosen the latter.
After all—
A Nimbus 2000.
For Hufflepuff's Seeker, that was no ordinary Christmas present.
It was practically an upgrade to his combat equipment.
Cedric even felt that if Gavin asked him to fly backward through three laps over the snow without clothes, he would seriously consider whether it was worth doing.
Gavin hadn't thought much of the expense at first. His Oxford scholarship alone gave him plenty to spend, never mind his family's "pocket money." But now that he had unexpectedly landed himself with a huge debt, he was seriously considering finding an excuse to get the broomstick back.
Everyone else, however, was completely lost. They had no idea what the two of them were hinting at.
Just as the mood threatened to turn back toward "what really happened," Neville came hurrying over.
"Gu!" he said. "Dumbledore wants to see you."
He was holding a small slip of paper, which he handed to Gavin when he reached him.
It read:
"Password: lemon and honey water."
"Thanks." Gavin put the note away.
Neville breathed a sigh of relief, as though he had finally delivered an important message. Then he added quietly:
"I'm glad you're back."
Gavin looked at him and nodded.
"Thanks, Neville."
With the others still watching curiously, he turned and left the Great Hall.
The Headmaster's Office looked much the same as ever.
Silver instruments gave off thin trails of smoke. Most of the portraits were pretending to sleep, and the Sorting Hat sat on its shelf looking thoroughly worn out.
Dumbledore sat behind his desk. When Gavin entered, he gestured for him to sit.
"Good afternoon, Gavin."
"Good afternoon, Professor. About the compensation..."
After the brief greeting, Gavin had meant to start by asking whether the compensation could be reduced.
The figure of three thousand five hundred and eighty Galleons had been rattling around his head lately like a ledger with a life of its own. It was hard to ignore.
But before he could continue, Dumbledore raised a hand.
"We can discuss the bill later," he said. "There's something else I'd rather know first."
Gavin had no choice but to set aside the bargaining for now.
Dumbledore studied him with an attention even more focused than usual.
"The Obscurus," he said. "How did you manage it in the end?"
"You mean, how I turned into an Obscurus and then managed to become a normal wizard again?"
"Yes," Dumbledore said. "That is the question that concerns me most right now."
For Dumbledore, it truly was.
The bill, the school rules, the tower, the aftermath—of course they all mattered, but they were ultimately minor problems for the school. If Gavin had truly found a method that could be understood, repeated, and perhaps even improved, and used it to go from an Obscurus back to his normal state—
Then its significance went far beyond the old Astronomy Tower. That, at least, was what Dumbledore believed.
Gavin was quiet for a while.
He had been thinking about the same question throughout his stay at St. Mungo's.
Whenever he had a spare moment, he wondered what the black whirlpool and the white whirlpool each represented.
And what about that "river"?
Why had stray thoughts flooded his mind when he tried to leave the black whirlpool?
And why had he been able to reconnect with his normal magic at a certain moment?
Those experiences, what he had read before, and what he understood from his previous life about meditation, the structure of consciousness, and models of cognition were slowly coming together into a hypothesis. It was still incomplete.
So he looked up at Dumbledore and began with a question that seemed unrelated.
"Professor," he said, "how much do you know about Indian Buddhism?"
Dumbledore blinked.
Gavin continued:
"Have you heard of the Manas Consciousness?"
Before you continue