Chapter 22

Tang Lingwumin savored the last sip of her milk tea, stared at the empty cup, stuffed it into her backpack, then led Zheng Fa upstairs.

“I drank your milk tea—this matter’s on me!”

She nearly patted her own bulging chest.

On the fourth floor, she stopped and pointed to a security door: “My teacher lives here. Wait outside while I go in and tell him.”

She knocked. The door opened. Tang Lingwumin gave Zheng Fa a “wait here” look, slipped through the gap, and left the door half-closed.

Zheng Fa waited behind the door; muffled voices drifted from inside.

“White Teacher, can I ask you a favor?” Tang Lingwumin’s voice was crystal clear.

Zheng Fa smirked.

That voice was way too sweet.

“Go ahead and say it.”

An old man’s voice replied, wary and sharp—Zheng Fa felt an odd sense of familiarity.

“I’ve brought you another student!”

“Are you dating someone?”

The old man’s voice shot up instantly.

“Dating? I mean, one of my classmates has a question for you.”

“A studious student? Male or female?” The old man clearly didn’t believe her.

“Male… but we’re definitely not dating!”

It was clear Tang Lingwumin was going all out for a milk tea.

“Pfft. I know exactly what these young kids are thinking. Most young men aren’t studious—they’re lecherous! I won’t agree.”

The old man clearly saw Tang Lingwumin as a junior.

He harbored suspicion toward every male near her.

“White Teacher, aren’t you a university professor? You’re supposed to answer questions and teach without discrimination!”

The old man snapped: “I’m retired! Do you understand retired? I taught students before retirement—do you think I’ll keep teaching after? Am I just wasting my retirement?”

This old man clearly resented his job.

In short—he was lazy.

“But teaching one student is teaching, and teaching another won’t hurt!”

Tang Lingwumin was truly pushing hard. Even from outside, Zheng Fa felt his skin crawl from her voice.

Hard to imagine such a tone coming from her slightly cold-faced expression.

“You’re different—you’ve got too much from your mom… no, I mean you have real talent in math! You’re smart!”

“Then if you never even meet him, how do you know he doesn’t have talent too?”

“Math talent? You just look at someone and you know right away if they don’t have it. It’s usually accurate.”

“...So this really can’t be done?”

“Absolutely not!”

…

Tang Lingwumin trudged out of the room, her face tinged with apology.

“Sorry—he doesn’t want to meet you.”

“It’s fine. You’ve tried your best.”

From outside, Zheng Fa could picture how Tang Lingwumin had pleaded and flattered the old man—her voice alone betrayed her effort.

Besides, that milk tea was meant as thanks for her bringing him here.

He’d also realized now: her family had spent a fortune to get her this teacher.

Twenty-eight yuan times a hundred still wouldn’t cover it.

He didn’t think he could demand a teacher just for a milk tea—he wasn’t that greedy.

“What if…” Tang Lingwumin glanced at her backpack, where the empty cup still sat, hesitating: “I buy you another milk tea?”

“No need. If you really feel bad, just ask me questions later. Can’t ask the teacher? Asking a student’s close enough.”

“Don’t worry—I will. I’ll definitely teach you!”

“Teach you? A milk tea bought you? He just wants an excuse to talk to you more!”

An old man’s voice came from behind her, exasperated.

Zheng Fa watched as a white curly head poked out from the door crack.

He recognized the familiar old face.

Zheng Fa suddenly understood—no wonder it sounded familiar!

…

Inside the room, the three sat on the living room sofa; the atmosphere grew awkward.

Zheng Fa and the white-haired old man—the same one from the park—both struggled to speak.

Tang Lingwumin looked confused, glancing between them, as if unsure how they’d all ended up inside.

“Um… Young Master.”

“Just call me Xiao Zheng or Student Zheng.”

Hearing “Young Master,” especially in front of Tang Lingwumin, made Zheng Fa feel intensely embarrassed.

“Alright then, Student Zheng. Don’t call me ‘you’ with all those honorifics. Call me Old Bai or White Teacher.” The old man pressed: “The person she mentioned—was it you?”

“Yes. I came across a few diagrams and wanted to show them to you, White Teacher.”

“No rush, no rush. You want to take remedial lessons with me?”

“I don’t dare hope to be your student—even just asking two questions would be enough.”

Zheng Fa said this apologetically, recalling the old man’s firm refusal earlier.

“No! I just thought about it—I’ve been a teacher my whole life. Now I’m retired, but my urge to teach won’t stop.”

Tang Lingwumin’s face was full of question marks.

Didn’t you just say the opposite?!

Zheng Fa was stunned, staring at the old man’s earnest face.

“So… what do you mean, White Teacher?”

“I mean—I’m a math guy. I only want to teach students with real talent. Young Master—no, Student Zheng—don’t your sects also seek out the most gifted to pass on secret techniques?”

“Huh?”

“Look at me…” White Teacher gestured to himself.

“I can tell at a glance—White Teacher, your bone structure is extraordinary!”

Zheng Fa suddenly understood.

“And I can see—you’re quite sharp in math too!”

Tang Lingwumin watched, utterly baffled.

These two men seemed to have just completed a shady deal right in front of her.

…

As White Teacher studied the diagrams Zheng Fa handed him, his brow furrowed, his expression turning serious.

For the first time, he looked like a real university professor—no longer the joker from before.

He traced his finger across the diagrams, then looked up at Zheng Fa:

“That’s all?”

“Yes.”

"I can't make sense of anything." White Teacher set the papers down. "Why don't you ask a fortune-teller? Let them figure out what these are by calculating with their fingers."

Zheng Fa: “...”

“But if you’re asking whether these patterns have any mathematical regularity—there is something.”

“Please explain.”

“This one, this one, and this one.” White Teacher pointed to three diagrams, uncertainly: “From the perspective of mathematical topology, they’re actually the same pattern.”

“Huh?”

Zheng Fa stared at the three diagrams.

Left, right—he couldn’t see any similarity.

“Topo… what?”

“That’s a basic, simple topology concept called homeomorphism…” White Teacher launched into his specialty, animated and eloquent.

After a long explanation, he paused and asked Zheng Fa: “Understood?”

“...”

Zheng Fa felt a tiny knowledge gnome had just tried to chisel open his skull—but somehow, his head had inexplicably developed iron skull skill.