I met my whole family through Baidu Tieba.

"I'm gone."

After standing at the entrance of the cafeteria for a while, Shen Kang said to He Qiuzhu, who was standing next to him, "I'm going to finish up some work at the other shops. You can go back to your dorm and have some fun by yourself."

Several of his stores are closing for the holiday today. There are a bunch of miscellaneous things to do, like giving speeches to employees and distributing New Year's red envelopes in advance.

Instead of letting He Qiuzhu run around with me and stand around doing nothing, it would be much better to let her go back to her dormitory and sit comfortably playing computer games, or lying in a fragrant and warm bed. Wouldn't that be much better?

"……oh."

He Qiuzhu was somewhat sullen.

She thought that Shen Kang had called her out to play with her.

However, Shen Kang had important business to attend to, so she didn't say anything. After saying "Oh," she moved and went back to her dormitory.

Shen Kang then started walking towards the south gate of the school. He walked all the way out of the school and went to Yangcheng Teachers College, where the shops were almost finished being renovated.

After spending some time at Yangcheng Teachers College, talking with the mentors, and giving them some red envelopes, Shen Kang received their affirmative answer: "Boss Shen, don't worry, come back next winter break, and these shops will be open immediately, with all the decorations, water and electricity in place."

After staying for a while, Shen Kang left Yangcheng Teachers College and returned to Yangcheng University of Science and Technology.

When I arrived at the south gate of Yangko University of Science and Technology, a phone call came in.

Shen Kang was taken aback when he saw the caller ID—it was Xia Meng, whom he had just eaten breakfast with that morning.

What does she want from me?

Shen Kang thought for a moment, then answered the phone and said "Feed".

There was no response on the other end of the phone, and a long silence followed.

Shen Kang thought he hadn't answered the call, so he took the phone off his ear to check it and make sure it was connected before putting it back to his ear. He wondered what was wrong with Xia Meng, that she wouldn't say anything when he called.

Just as Shen Kang was about to ask the other party what was wrong, Xia Meng's voice finally came from the other end of the phone.

"...Shen Kang."

In those two short words, Shen Kang heard a complex mix of emotions: resentment, helplessness, anger, reproach, hesitation... the emotions were practically piled up like a pie chart.

In short, it can be summed up in one word—indecisive.

I'm really torn.

Shen Kang was very kind, but didn't ask any further questions, only asking, "Is something the matter?"

Instead of answering, Xia Meng on the other end of the phone asked, "Do you know what He Qiuzhu is doing?"

Shen Kang said, "He's probably playing computer games in his dorm."

Xia Meng on the other end of the phone fell silent again, seemingly hesitating whether or not to say what she was going to say next.

But in the end, he sighed and said it.

"She was indeed in front of the computer, but she wasn't playing on it."

"So what is she doing?"

"Knocking on your door..."

Once Xia Meng started talking, she didn't hesitate any longer and told the whole story.

Through Xia Meng's narration, Shen Kang also learned some things.

The story begins a month ago.

She couldn't quite remember the exact date. She only remembered that when she returned to her dorm and pushed open the door, the other two weren't there; only He Qiuzhu was sitting at her desk, facing the computer.

The dormitory lights weren't on; only the screen's light illuminated He Qiuzhu's face. She sat there quietly, motionless, like a small sculpture.

Xia Meng called her name casually, but He Qiuzhu didn't respond.

Only when you get closer can you see clearly that she wasn't daydreaming, but staring at the screen. But there was nothing on the screen—not "nothing at all," but a black screen with a few lines of white characters printed on it, like the interface of some kind of old terminal.

Xia Meng glanced at it but didn't understand. What was "64 byt", what was "time = 3m", what was "ttl = 64"? Line after line, neatly arranged, like some kind of ritualistic prayer.

She asked He Qiuzhu, "What are you looking at?"

He Qiuzhu's shoulder twitched slightly, as if she had been startled awake.

Then, He Qiuzhu minimized the black window, turned her face, and said, "It's nothing." Her voice was very soft, almost inaudible.

Xia Meng didn't press further, after all, that's just He Qiuzhu's personality; if she doesn't want to talk, no one can get her to open her mouth.

Xia Meng encountered this scenario several more times later.

Sometimes He Qiuzhu was alone in the dormitory, and sometimes Fu Rong and Du Nanxin were there too, but the situation was always the same—He Qiuzhu sat in front of the computer with a dark window open on the screen, staring at it as if she was waiting for something.

Fu Rong asked, and Du Nanxin asked too. He Qiuzhu's answer was always the same two words: "It's nothing."

Nobody could figure out what it was.

When they first entered university, Fu Rong and Du Nanxin's understanding of computers was limited to surfing the internet and writing documents.

Xia Meng fared slightly better, but only to a limited extent. Those few lines of white characters were like gibberish to them, their meaning completely incomprehensible.

But Xia Meng kept it in mind.

She always felt there was something strange about that scene.

It wasn't because of the characters themselves, but because of He Qiuzhu's expression as she stared at the screen.

Xia Meng didn't know how to describe that expression—it wasn't the relaxation of watching a video, the focus of writing code, or the casualness of browsing the web; it was a very quiet expression, as if it contained something.

It's like they're guarding something.

One day, Xia Meng finally couldn't hold back any longer. She memorized the keywords she had glimpsed that time—pn, ttl, tm, 64byt—and then went to find a senior student in the computer science department.

The senior student laughed when he heard this and said that it was not difficult at all. The pn command is used to test network connection. You send a packet to an address and see if the other party responds.

Xia Meng asked, "So what does that line of text mean?"

The senior student said, "That line of text means—the other party is online. The computer is on, the internet is working, and there's a response."

The senior student even demonstrated it to her again.

The senior student opened a black window, entered a line of commands, pressed Enter, and the screen began to display line by line: reply from a certain address, number of bytes, time in milliseconds, and time to live.

The same.

Xia Meng stared at the black window for a long time.

The senior student next to me said enthusiastically, "If you want to try it, you can try it too. Just find any website, use a VPN to search for it or something."

Xia Meng shook her head, said thank you, and left.

She finally realized what He Qiuzhu was looking at.

But this didn't make her feel relieved. On the contrary, after understanding it, a deeper confusion welled up inside her. Because PN was too simple, so simple that it had almost no practical value.

It is not a chat tool, not a monitoring tool, and not any channel for obtaining information.

It has only one function: to ask "Are you there?" and then wait for the other party's reply.

"I am here".

That's it.

For the next few days, Xia Meng kept the matter to herself and didn't tell anyone.

She pondered it for a long time after returning to her dormitory.

He Qiuzhu is undoubtedly a top student. She learns at an incredibly fast pace, and not just by rote memorization, but by combining theory with practice.

For example, once, a computer in the next dorm broke down, and nobody knew how to fix it. In the end, they went to Xia Meng's dorm. After all, Xia Meng and her friends are computer science majors, so maybe they could fix it?

However, Xia Meng and her friends were only freshmen. They could handle some simple computer problems, but on that occasion, they couldn't understand the other party's computer malfunction.

In the end, He Qiuzhu stepped in, tapped a few keys, and popped up some "ancient windows" that no one could understand. She finished the job in no time.

After that incident, Xia Meng knew that her older sister was a master.

Sometimes, Xia Meng even doubted whether she and her friend actually went to the same school.

But that's normal, after all, she's the older sister, it's normal for her to be a bit more assertive!

Perhaps it is because of this kind of filter that Xia Mengjue, a computer genius like her sister, could easily hack into other people's computers?

She should be able to see whatever she wants, whose computer she wants to look at, and whatever content she wants to see with ease, right?

But she didn't.

She did nothing. She simply opened a black window, typed in a command, and sat there watching the "Reply" messages pop up one by one. When they appeared, she felt relieved. When they stopped, she waited.

She wouldn't go in.

She doesn't look through anything.

She was just knocking on the door.

She knocked once, heard a sound inside, and knew someone was inside, which put her at ease.

Tap it again in a little while...

Xia Meng didn't even need to ask; everyone knew who that bastard behind that p was—besides Shen Kang, who else could make He Qiuzhu act like this?

Xia Meng kept this a secret for a whole month and didn't tell anyone.

She didn't know whether she should tell anyone, or if telling anyone would be meddling. He Qiuzhu certainly didn't want anyone to know, otherwise she wouldn't have kept it from Fu Rong and Du Nanxin.

But today, Xia Meng suddenly wanted to tell Shen Kang.

Just now, after everyone parted ways at the cafeteria entrance, Xia Meng left the school, took the bus to the train station, and while idly checking her QQ, she discovered that He Qiuzhu's QQ showed that she was online on her computer.

This made Xia Meng very happy—logically speaking, shouldn't she be with that bastard Shen Kang at this time? How come she's online on her computer?

So Xia Meng sent a message to He Qiuzhu and chatted with her. She also asked about it and found out that Shen Kang had something important to do, so He Qiuzhu went back to the dormitory alone first.

After chatting for a while, He Qiuzhu's texting frequency noticeably slowed down, replying only once every few hours.

Xia Meng easily deduced from the frequency that He Qiuzhu was "knocking on the door" again.

This made Xia Meng furious with Shen Kang. She immediately wanted to tell Shen Kang about this and scold him again, asking him what kind of man he was.

But then I thought, wouldn't what I did actually help Shen Kang and He Qiuzhu get along? What's the difference between this and helping my rival get ahead?

No way, my sister is mine! ...

That's why Xia Meng's voice sounded so hesitant just now.

However, after much hesitation and struggle, Xia Meng finally decided to tell Shen Kang about it—as long as her sister is happy, that's all that matters.

……

Shen Kang listened intently on the other end of the line.

In my mind, I already have that image:

A girl sat in front of a computer, staring blankly at the numbers displayed in a dark, old-fashioned window.

There may still be some sounds coming from its mouth.

"Knock knock knock, are you home?"

Seeing the reply message displayed on the window, showing that the other party is online, she might have a bright, sparkling smile.

Seeing the connection timeout message on the window, indicating that the other party is offline, she might rest her chin on her hand, stare blankly at the screen, and imagine what the other party is doing right now...

This is fatal.

After being shocked by He Qiuzhu's technical abilities that day, Shen Kang now understands very well that He Qiuzhu is fully capable of hacking into his computer, seeing what he is doing in real time, and even controlling his computer. It should be a piece of cake for He Qiuzhu.

But she didn't do that.

When she just wanted to think about herself, she would stand outside the door, knock cautiously, and ask, "Is anyone home?"

Shen Kang stuffed his phone back into his pocket and stood at the south gate, not moving for a long time.

Students dragged their suitcases past him, and some who knew him greeted him, but he didn't respond. It wasn't that he didn't want to; he simply didn't hear them. His ears were ringing, as if someone had struck a bell in his head, the echo reverberating and making his entire brain tingle.

He smoked in his past life, but quit in this one. He quit on the very first day of his rebirth and hasn't touched a single cigarette. He feels that since he's been given a second chance at life, he should take good care of his health.

But now he wants to smoke one.

The thought suddenly popped up from somewhere deep within him, as if something had pulled him up from the depths. It wasn't a craving, nor a habit; it was a more fundamental, almost physiological need. He felt a tightness in his chest, a stiffness in his throat, and a strange emptiness in his fingertips, as if something was missing. He stood there pondering for a long time before realizing—he needed a cigarette.

He looked up at the security booth next to the south gate. Sitting at the entrance of the booth was an old man in uniform, around fifty years old, with a cigarette smoldering in his hand, squinting in the sun.

It wasn't one of the security guards he knew.

Shen Kang walked over.

"Master," he heard his voice was a little dry, "could I borrow a cigarette?"

The old man looked up at him, probably noticing something in his expression. Without asking any questions, he took out a crumpled pack of Hongtashan cigarettes from his pocket, shook one out, and handed it over, along with a lighter.

"Young man, did you fail your final exams?"

Shen Kang took the cigarette, put it in his mouth, and mumbled "No."

It took him three tries to light the lighter. The moment the flame shot up, he took a drag, and the smoke filled his lungs. The familiar yet unfamiliar sensation made his throat instinctively contract.

"That means you've been dumped," the old man said confidently, leaning back in his chair and exhaling a puff of smoke.

Shen Kang did not respond.

He leaned against the doorframe of the security room, took another drag, and slowly exhaled the smoke, watching it dissipate in the winter wind, squinting his eyes.

My firm belief is wavering a bit; I need to find a way to strengthen it.