Dumbledore had house-elves serve two cups of tea. Sterling took a sip and grimaced. Not much sugar, quite bitter.
"I went to his house according to the address in the letter. Lots of dust covering everything. Roughly estimated, no one had lived there for about two months. This coincidentally matches the Halloween timeframe of the last letter."
"I assume you received other news as well?" Sterling asked. Just this discovery alone couldn't account for Dumbledore being missing all day.
"Some speculation, yes." Dumbledore brought over a newspaper from the bookshelf and spread it before Sterling.
The scarlet headline was conspicuous and alarming:
"Dark Wizard from a Century Ago Returns? New Era Dark Wizard's Imitation?"
"Professor, what does this refer to?"
"Jack the Ripper." Dumbledore closed the newspaper with deliberate care. "In the Muggle world, he once left a series of inexplicable bloody cases, was finally captured by the Auror Office and ultimately died in Azkaban."
"So the newspaper means a new Jack the Ripper has appeared?"
"Exactly. The first imitation case appeared around September. Three cases total so far."
Sterling felt relieved hearing it started in September. After Andrew's disappearance, Dumbledore mentioning Jack the Ripper obviously wasn't changing subjects. If it had started in October, it might point to a situation Sterling didn't want to accept.
Wait, from September to now in late December should be four months. According to mystery novels Sterling had read, serial killers usually followed certain patterns.
"He kills one person per month?"
Dumbledore nodded heavily, his expression grave.
"But that's impossible. He wrote me a letter yesterday."
"Yes, he may indeed not have been harmed yet, but Sterling, don't you feel something's wrong?"
Dumbledore tapped the table, moving the alchemical figure holding letters to face him directly.
"Think about it. Even without memories, you should have vague feelings. Does that Christmas letter really match your impression of Andrew?"
"Why can't you see all other letters, yet can see just this one? I've thoroughly examined this letter. Materials identical to previous ones, no magical traces whatsoever."
"Other letters, even placed before you, you'd subconsciously ignore. Why is this letter an exception?"
Dumbledore clasped his hands, his half-moon glasses reflecting the firelight.
"Either whoever caused your forgetting deliberately lifted restrictions on this letter, or someone else wrote it falsely using Andrew's name, naturally unaffected by the forgetting magic."
Sterling couldn't refute the logic. After Dumbledore pointed it out, he quickly grasped the horrible reality.
"That new era Jack the Ripper also has forgetting abilities? This power..."
"Tom." Dumbledore nodded grimly. "Speaking of which, my first reaction was also Tom's Killing Curse, but there's one critical difference. Tom's forgetting range is incredibly vast. If it were truly Tom..."
"Neither you nor I could possibly still remember Andrew."
"And that so-called Jack the Ripper, according to Ministry intelligence, has special means to block others' memories, more similar to your current condition."
"Professor Dumbledore, may I search for him myself?"
"Very sorry, Sterling." Dumbledore shook his head decisively, leaving no room for negotiation.
"However I think about it, Jack the Ripper has no reason to target Mr Dept except for you."
"Perhaps we can extract some information from this letter."
Dumbledore pulled out the letter Sterling had entrusted to him, spreading it carefully on the table.
"Mr Dept is a Squib. Yes, you should understand by now. Squibs are children born in wizarding families without spellcasting talent."
"They don't lack magic power, but it's too weak to leave their bodies. So they can use potions and alchemical items normally, but otherwise are no different from Muggles."
"To this day, no method exists to give Squibs spellcasting ability."
Sterling nodded. According to Robert, Mr Filch was a Squib, though he rejected potions and alchemical items for unknown reasons.
"This might give us a hint. The present world doesn't have such methods, but Avalon might. This is one reason I won't let you leave school. I suspect someone may have emerged from there."
"If you're at school, I trust Hogwarts' defences can delay any threat until I return, but outside, I'd be powerless to help."
Dumbledore had never looked at Sterling with such serious intensity. Sterling felt the full weight of pressure from this old man, the most powerful wizard of his time.
His meaning was clear. Even if a great wizard from Avalon came to the present world, he possessed the power to stop their actions.
Dumbledore softened his tone slightly.
"Of course, another reason for staying is that remaining at school might be the fastest way to see Andrew. Notice the last line? He says he'll return to find you."
"Meaning he'll come to Hogwarts."
"Whether this 'he' is the mastermind or Andrew himself, you need only study well at school. They'll come to you."
"I heard from Minerva you're practising Animagus? Excellent. I believe your talent in this magic is absolutely exceptional. If you encounter difficulties, feel free to ask me, though you'd better consult Minerva first."
"Otherwise she might complain I stole her prize student."
Dumbledore winked playfully as before, but the atmosphere didn't lighten as he'd hoped.
Sterling couldn't help wondering how many burdens he had to shoulder.
Gerda's sister-finding adventure, locating Ravenclaw's secret chamber, waiting for the mastermind, guarding against Voldemort lurking somewhere, solving Galahad's mystery...
How old was Sterling now? Still in the first year. Sterling had thought he was mature beyond his years, but perhaps he'd been mistaken.
"Perhaps you'd like to spend a pleasant Christmas with friends?" Dumbledore suggested gently.
This was obviously a polite way of ending the conversation. Sterling wasn't obtuse enough to miss the hint, but before leaving, he had one final question for Dumbledore.
"Excellent suggestion, but Professor Dumbledore, I have one last question. Room of Requirement – does this name ring a bell?"
"Oh? That's quite a secret place."
"But I happen to know more than most. You've actually passed Hogwarts' secret many times at its entrance."
Dumbledore made a circling gesture with his finger.
"Remember a tapestry of a troll clubbing a wizard? Walk back and forth three times in front of it, firmly repeating in your mind what kind of room you need, and then the wall opposite the tapestry will open a door for you."