Dilys Derwent knew very well what a Horcrux was.
"What exactly is it, then?" Phineas Nigellus demanded irritably.
"As a fellow Headmaster, how is it that you know while I don't? It makes me look rather foolish, doesn't it?"
"Idiot," Derwent snapped. "What did you even do when you were alive? Spend all your time tormenting students instead of studying magic?"
Phineas was so thoroughly scolded he could not lift his head. The other portraits—those who had no idea what a Horcrux was either—shifted their gazes awkwardly, avoiding the subject.
"Enough, Derwent," Dumbledore interjected gently. "Horcruxes are exceedingly rare. It is perfectly natural that most would not know of them."
The heavy-nosed Modycurs Egerton stepped forward to smooth things over. He began to explain to the others the purpose of a Horcrux, as well as the general method of its creation. By the time he was finished, every face in every frame had darkened with horror.
Armando Dippet looked the worst of all. His complexion had gone chalk white.
A student had created something so vile right under his very nose, and he had never noticed a thing. Worse—he had admired young Tom Riddle. Praised him. Encouraged him.
"I misjudged him… I misjudged him so badly…" the old man muttered, trembling, his voice choked with anger at himself.
"Armando, this was not your fault alone," Dumbledore reassured him. "I was at the school as well, and I too noticed nothing. Now is not the time for regret. We must focus on what is to be done."
"What's to be done? Isn't it obvious?" Phineas shouted. "Destroy the Horcrux, then kill the body of Voldemort! Right now he's just a scrap of soul—less than a ghost!"
"Horcruxes are not so easily destroyed," Derwent countered, frowning deeply. "Perhaps the Killing Curse might suffice—but that carries its own risks. Fiendfyre could also work, though it is perilous beyond measure."
"Let's not rush," Dumbledore said calmly, setting the diary aside. "This is a rare opportunity. Through this Horcrux, I may learn more of Voldemort's thoughts. Mr. Riddle has indeed done me a great service."
At this, a faint smile touched his lips.
For years, Dumbledore had suspected that Voldemort had made Horcruxes. Now, at last, he had proof. More than that—he held in his hands a living fragment of Voldemort himself. With this, he might glean secrets untold.
And yet, deep inside, unease coiled like a serpent.
Tom had explained how Ginny Weasley had received the diary—slipped secretly into her schoolbooks. Nearly certain, then, that Lucius Malfoy had planted it. Revenge, most likely, for Arthur Weasley's raid on Malfoy Manor the previous summer.
But one thing was clear: Lucius could not have known what the diary truly was. Voldemort would never share the secret of immortality with anyone. If Lucius had known the diary's significance, he would never have dared use it as a petty weapon.
Dumbledore's mind raced through the structure of the Death Eaters. Lucius had always maintained a high position—wealth, political ties, charm. But he was never in the innermost circle. Voldemort's most guarded secrets would not be entrusted to him.
So why, then, had he been given this Horcrux?
The answer came to Dumbledore with chilling clarity.
Because this was not the only one.
Voldemort had created more.
"Ah, Tom…" Dumbledore thought grimly. "You've given me a riddle far greater than you know."
Meanwhile, far from the Headmaster's office, Tom himself sat in the Slytherin dormitory, wearing an exasperated expression.
Because he was the one now being given headaches.
[Rouse: Boss, these classes are dull. Isn't there something more exciting you can send my way?]
[Tom: You don't think being Defense Against the Dark Arts professor is exciting enough? Don't forget—the post is cursed.]
[Rouse: That only matters if I stick around for a full year. If I quit before then, I'm fine. But really, boss—school is boring. You've got the right idea, going after pure-blood families. That's real fun.]
[Tom: If you want something thrilling, then gather dirt on the old pure-blood clans in North America. I have fewer channels for information across the ocean.]
In his staff quarters, Rouse' eyes lit up instantly. Now that's an idea.
[Rouse: You can count on me. I know plenty of dirt—especially about the Graves family. But wait, with their size and influence, they wouldn't even qualify for a proper entry, would they?]
[Tom: The Twelve Auror Families will be written up together. If the Graves are included, it will elevate the story.]
[Rouse: Brilliant, boss! And don't forget to include Lord Grindelwald's masquerade as Percival Graves. Oh, and be sure to write about how I stole Robert's wife. That deserves a place in history, doesn't it?]
Tom: …
Sometimes he wondered if Rouse was simply deranged. Once this man bore a grudge, he would keep poking at it from morning till night.
[Tom: If you can handle Robert's wrath, I'll write it in.]
[Tom: And if you're still bored, then stir up the students instead. Don't you think there's far too little interaction between magical schools these days? Use your Ilvermorny contacts—see if you can bring a few students here for an exchange. That should liven things up.]
Rouse practically vibrated with excitement.
During his own school years, Ilvermorny had always boasted of being the world's greatest magical academy. But internationally, the claim had never carried much weight. How could it, when Dumbledore's very presence kept Hogwarts at the forefront?
But if Ilvermorny students were brought face-to-face with Hogwarts… sparks would fly. Duels, rivalries, challenges—it would be chaos. Delicious chaos.
Tom had no idea that, with just a few words, he had flipped a switch in Rouse' mind. A switch that, in time, would make Tom himself the target of Rouse' endless "fun."