"Interested? No, no, no…" Slughorn shook his head hastily, his words spilling out in a rush. "What I mean is… I do have some interest in antiquities like these…"
As he spoke, his eyes never really left the direction of Jon's pocket.
From the look on his face, Jon could be fairly certain of one thing… he'd taken the bait.
"Professor Slughorn, the situation is actually like this—" Mrs. Greengrass, clearly running out of patience, cut in. "Mr. Hart hopes to consult you on a question…"
"Consult me?" Horace Slughorn's expression changed instantly. He shot a guarded look at Diana Greengrass, then at Jon, before refusing coldly. "Hmph! I'm not a Hogwarts professor yet. I intend to enjoy a few more days of peace and quiet!"
It was obvious that Slughorn's wariness was even stronger than Jon and Mrs. Greengrass had expected.
As Tom Riddle's former mentor—and one of the very few wizards who knew Riddle's true identity—Horace Slughorn was extremely sensitive about his past. On the one hand, he feared the Death Eaters might try to use it to draw him in; on the other, he worried the Ministry of Magic might one day use it against him. Because of that, even the slightest slip from Mrs. Greengrass hadn't escaped his notice.
Mrs. Greengrass's face stiffened as she realized she had only made things worse. She quickly shot Jon a subtle, pleading look.
"Yes, just academic matters," Jon said calmly, his expression unchanging as he continued rummaging through his briefcase.
Slughorn eyed him with open suspicion, and then—
"Would you care to look at this?" Jon took out a small crystal vial filled with a transparent liquid and handed it over.
"This is…" Slughorn's expression gradually eased. He drew his wand and gently tapped the vial with it, then even tipped out a single drop onto his hand, licked it lightly, and spat it out.
"Veritaserum… Looks like a novice's work. Too much Jobberknoll feather, the Sri Lankan vulture bile wasn't refined finely enough, and you used ferret heart tendon—stone marten tendon would've been better. Honestly, there are plenty of flaws!"
Decades of teaching Potions kicked in, and he instinctively began critiquing the little vial.
Setting it down again, Slughorn lifted his head and studied the boy in front of him.
"You brewed this?" There was a note of disbelief in his voice.
"Yes," Jon nodded.
"Merlin's beard!" Slughorn stared at Jon for a long moment before muttering, "How old are you, exactly…?"
"I'll be fifteen in a few days," Jon replied with a small smile.
"Fifteen, and you haven't even taken your O.W.L.s yet… The potion's a bit rough, but brewing Veritaserum at your age is an impressive achievement. Dumbledore's praise of you wasn't misplaced at all," Slughorn said, unable to hide his admiration.
He wasn't wrong. This bottle had been Jon's very first attempt at a high-level potion, back when his technique was still unpolished. If he brewed it now, the result would be vastly better.
Naturally, Jon had no intention of saying that out loud. It was enough that Slughorn had begun to take him seriously.
...
"I'm still nowhere near your level," Jon said smoothly, putting the vial back into his briefcase as he laid on the praise. "Professor Dumbledore once said you're the finest Potions Master Britain has produced this century. Even our former Potions professor, Professor Snape, can't compare to you."
"Oh? Is that so?" Slughorn was clearly enjoying himself now, nodding with a pleased smile. "I didn't realize Professor Dumbledore thought so highly of me… No wonder he wants me back in the classroom."
"That's precisely why I came today, out of respect, to seek your guidance," Jon said. After all the circling around, he finally revealed his true purpose.
"Only questions related to Potions," Slughorn said flatly.
"Of course. Academic matters only," Jon agreed with a nod. "Actually, I was hoping to propose a little competition."
"A competition? Hahaha!" Slughorn burst out laughing. "No offense, but you're barely old enough to—"
"Just a figure of speech," Jon said calmly. "My real goal is to learn. I'd like us to brew the same potion and let me see the gap between us, so I can learn something from it. I'm no longer a Hogwarts student, after all. Opportunities like this won't come often."
Seeing the faintly dismissive look in Slughorn's eyes, he added, "I noticed you were quite interested in that locket I took out earlier. If I lose, I'll give it to you as the stake."
Slughorn's breathing grew heavier.
"And if I lose?" he asked gruffly.
"To be honest, I've never really considered that I might win," Jon said unhurriedly. "If that happens, you can simply answer one academic question of mine."
Slughorn studied Jon carefully, clearly sensing there might be a trap somewhere in those words. Still, the temptation of a Slytherin relic was far too strong to ignore.
Besides, he had absolute confidence in his skill with Potions. He simply couldn't imagine losing to a boy who wasn't even fifteen yet.
He nodded. "I agree to your terms. But I'll only answer questions related to academics. If you ask anything else—about my past or my personal affairs—I will not answer."
"Of course," Jon said, nodding again. "I can swear to it. We can even make an Unbreakable Vow."
"I'd recommend the two of you do just that," Mrs. Greengrass said with a gentle smile. "Just in case Mr. Hart tries to wriggle out of it if he loses, or hands over a counterfeit instead, Professor Slughorn."
"No problem," Slughorn said after a brief hesitation, nodding.
"Then I'll act as the witness," Mrs. Greengrass offered.
...
Horace Slughorn and Jon Hart clasped each other's right hands.
Diana Greengrass raised her wand and placed its tip against their joined hands.
"Mr. Hart," Slughorn said, "do you agree to a Potions competition with me? If you win, you will give me the Slytherin relic I saw earlier."
"I agree," Jon said, nodding.
A thin, dazzling tongue of flame shot from the wand, like a red-hot wire, winding around their clasped hands.
"Professor Slughorn," Jon continued, "if you lose, you will answer one academic question of mine."
"I agree," Slughorn replied.
A second tongue of flame burst forth, intertwining with the first to form a slender chain glowing red.
He added, "Your question must be strictly academic. It must not involve my past."
"I understand," Jon said, nodding once more.
A third tongue of flame erupted from the wand, weaving tightly with the other two and coiling around their joined hands like a rope—like a fire-breathing serpent.
Bathed in the glow of the three flames, a faint smile curved Jon's lips.