Grandfather Paradox

Gu Wanqing looked at the man in a white lab coat standing before her, panting heavily as if struggling to catch his breath, with a hint of surprise in her eyes.

"……"

"You are……"

"I’m from Yinshan Academy… the school doctor at the third infirmary… and, well, I also counsel students on… huff… their psychological issues." Ye Shuang tried to steady his breathing before straightening up slightly. "Could you come down first, please?"

"There’s still so much beauty in this world. Don’t make a rash decision."

"……" Gu Wanqing’s face was covered in bruises and scars. She glanced at Ye Shuang briefly before turning away.

"No need…"

"Thank you…"

The wind on the rooftop was fierce, as if burying her frail voice within its gusts.

After uttering those words, she leaped off without hesitation.

"W-Wait?!"

Ye Shuang rushed to the railing and looked down, just in time to hear the sickening thud of the girl’s body hitting the ground.

Ye Shuang: "……"

"Why?" His fist slammed against the railing before he spun around and bolted downstairs—but just then, he noticed the clock in the upper right corner ticking toward twelve.

Tick. It landed precisely on the twelfth mark.

"Bzzz—"

Another sharp, buzzing noise pierced his ears as his vision dissolved into blinding white light.

……

……

"School doctor?" Everything around him seemed to have returned to the infirmary. Gu Manman was now sitting in a chair, giving him a puzzled look. "Did you… zone out?"

"……"

"……"

"My apologies…" Ye Shuang rubbed his throbbing temples and glanced at the virtual clock, which had rewound itself.

Ye Shuang: "……"

"Right, go on," he said, addressing the girl who claimed to be Gu Wanqing’s cousin.

"Like I was saying earlier, my cousin had a terrible relationship with her uncle’s family. They abused her regularly." Gu Manman continued, "Her suicide… it’s definitely tied to them. If possible, I hope you can share this with the reporters."

"I see." Ye Shuang nodded.

Twenty minutes later…

"Thank you, school doctor. I feel much better after talking to you."

"Don’t mention it."

"I’ll head back now. Goodbye."

"Take care."

After she left, Ye Shuang stared at the countdown clock, baffled. What had just happened?

A hallucination?

Unlikely.

Time travel?

Since when did this thing have that kind of power?

But based on what had just occurred, Ye Shuang pieced together a few things—

The countdown clock seemed to function like a rechargeable battery. Once he entered that time-warping state, the clock would start moving forward again.

Once the hour hand struck twelve, he’d return.

"Haah… If this is real, what’s the point of such a short window?" Ye Shuang estimated that the time he’d spent climbing the stairs and talking to the girl was roughly ten minutes.

Ten minutes—could that really change anything?

No…

Ten minutes could.

Even if it was just calling his parents back then, telling them to leave two minutes later, or reassuring them not to come looking for him…

Ye Shuang’s entire body prickled with goosebumps.

It’s possible…

It’s possible…

He stood up, his breathing erratic as he paced back and forth in the infirmary, rubbing his hands together. His mind raced, replaying every detail to ensure he missed nothing.

"What’s wrong with you? You look insane." An Shiyu’s voice cut in from the side. She’d never seen him so unhinged before—like he’d lost his mind after that conversation.

Ye Shuang suddenly seemed to remember something and lunged at An Shiyu, gripping her shoulders.

"An Shiyu!"

"What the hell?!" She recoiled, her face flushing as she struggled against his hold before finally kicking him square in the stomach.

"Get a grip!"

Ye Shuang collapsed to the floor, laughing hysterically. "Hahahaha… If it’s really possible…"

"……" An Shiyu shot him a disgusted look and muttered something in dialect.

Then she added,

"So what if you were too slow to reach the rooftop? It’s not your fault. Why are you acting like a lunatic?"

Ye Shuang’s expression instantly stilled—so calm it was unsettling. He stared at her. "What… did you just say?"

"Huh?" An Shiyu frowned, wondering if his ears were malfunctioning too.

"Why are you acting like a lunatic?"

"No, before that…"

"You didn’t make it to the roof."

"I did!" Ye Shuang insisted.

"Tch, so you’re saying I misremembered?" An Shiyu gave him a deadpan look. "Weren’t you the one who just said you saw her fall from the window because you didn’t get there in time? Old man, are you senile?"

Ye Shuang fell silent.

He stood up, pulled out his chair, and sat down. The infirmary plunged into an eerie quiet.

"……" An Shiyu crossed her arms, studying him.

After witnessing his manic laughter followed by this deathly stillness, she couldn’t help but ask, "Old man… what’s wrong with you?"

"Let me ask you something," Ye Shuang suddenly said.

"Mm?"

"If someone travels back in time, changes something, and returns, would the future change?"

"Probably trigger the butterfly effect," An Shiyu mused.

The butterfly effect—where even the tiniest change could set off an enormous chain reaction.

"Then why hasn’t anything changed? Even though… Was it just a simulation?" Ye Shuang muttered to himself.

The emotional whiplash left him nauseous.

Just then, An Shiyu added, "But not necessarily. Maybe the future stays exactly the same."

"Why?" Ye Shuang blinked.

An Shiyu eyed him curiously, wondering why he’d suddenly taken an interest in this topic.

"Ever heard of the grandfather paradox?"

"If you go back in time and kill your grandfather, then your grandfather wouldn’t have your father, and your father wouldn’t have you. But if you were never born, how could you have traveled back to kill your grandfather in the first place?"

"So, the more widely accepted theory is that killing your grandfather would create a new timeline—like a branch sprouting from a tree. The original timeline you return to remains unchanged. Only the new one diverges."

Ye Shuang: "……"

So, does that mean nothing will change in the future?

No… wait, if a new timeline really emerges, even though my own future won’t change, my parents could have a new future—they could live well in another world.

An Shiyu’s words ignited a fire in Ye Shuang’s heart.