Song Qinglan hung up the phone and returned to the library from the secluded hallway.

The library was a modern building, its interior shaped like a cone. The transparent staircases were designed with the concept of a Penrose staircase, featuring large mechanisms that allowed visitors to access different floors.

Through the shifting staircases, Song Qinglan spotted Ji Yushi sitting at a table, deeply engrossed in reading.

A tall stack of books was piled up beside Ji Yushi, indicating that he wouldn’t be moving anytime soon. He didn’t need to take notes while reading, and his page-turning speed was faster than most people’s, yet his expression was more focused than anyone else’s.

It’s said that people with hyperthymesia can vividly recall every detail of their lives, from major world events to the smallest thoughts in their minds. They have an insatiable thirst for knowledge, making them naturally inclined to become geniuses of a certain kind.

But for the first time, Song Qinglan found himself wishing Ji Yushi were just an ordinary person.

Someone who might misread questions out of carelessness, forget to feed his cat in the rush to leave home, or run into a high school classmate on the street but fail to remember their name.

Ji Yushi sat quietly beside the massive, seemingly endless bookshelf.

He looked relaxed.

During these few days of vacation, he was happier than he had ever been.

“What’s wrong?”

Noticing Song Qinglan’s return, Ji Yushi looked up and asked, his dark eyes clear and pure.

Ji Yushi.

His original name was Sheng Han.

Suddenly, those eyes overlapped with the eyes of a child from long ago.

Song Qinglan had an epiphany, recalling the kindergarten at Ning University’s affiliated school, the little girl whose face he could barely remember, and the joke he made about his “first love”… All along the way, Ji Yushi had dropped hints, but knowing Ji Yushi’s vengeful and mischievous nature, he was likely still holding a grudge over being mistaken for a little girl and decided to tease him.

Song Qinglan pulled out the chair beside him and sat down.

This floor was sparsely populated, and they were the only ones at the long table.

Time flowed on, always moving forward.

The naive children of the past had grown into mature men, and two lives that had briefly intersected years ago had somehow crossed paths again after more than a decade.

The wonders of time and the extraordinary nature of fate stirred something powerful within Song Qinglan. He directly asked, “When did you recognize me?”

Ji Yushi looked puzzled. “Recognize you when?”

There was a trace of amusement in Song Qinglan’s eyes, mixed with a hint of helpless reproach, as if he couldn’t help but be exasperated. “When did you realize I was the chubby little boy who used to chase you around in kindergarten?”

Song Qinglan pulled Ji Yushi’s hand away, closing the book in front of him.

Forcing him to focus solely on him.

“Han Han.”

Ji Yushi was slightly startled. “How did you…”

But Song Qinglan interrupted, asking, “Why were you wearing a dress when you were a kid?”

Ji Yushi: “…”

Song Qinglan pressed on, “Consultant Ji, you were cross-dressing as a boy and deceiving my feelings when we were just kids. You even ‘bent’ me at such a young age. Don’t you think you should take responsibility?”

Ji Yushi paused in his breath, reluctantly explaining, “That was for a performance, not cross-dressing! It’s your own fault for not being able to tell the difference between boys and girls. How was I supposed to know you thought I was a girl?”

Ignoring the disdain, Song Qinglan continued his accusations, “You even cried when I left.”

“I didn’t.”

“You did.”

“I didn’t.”

“You did.”

It was as if they had suddenly returned to kindergarten, engaging in a childish back-and-forth for several rounds until Song Qinglan sealed Ji Yushi’s lips with a kiss, bringing the exchange to an end.

They kissed in the quiet, deserted library.

Their lips and tongues intertwined, tender and gentle.

The glass reflected their kissing figures.

After the kiss, Song Qinglan rested his forehead against Ji Yushi’s and asked once more, “When did you recognize me?”

This time, Ji Yushi answered the question directly, “The first time we met in Jiangcheng.”

That time, when he and Minister Wang were touring the base, they heard someone push open the door and enter.

The person who entered was tall, with long legs, a handsome face, and an air of arrogance that was somewhat off-putting.

“His name is Song Qinglan. ‘Qinglan’ as in ‘clear sunlight, mountain wind’…”

A person’s face may change as they grow, but the general features remain recognizable, especially to someone like Ji Yushi, who is like a walking facial recognition device. He initially had doubts, thinking it was too coincidental, but after Minister Wang introduced him, he confirmed the answer.

“Damn,” Song Qinglan couldn’t help but curse with a laugh. “Why didn’t you tell me then?”

Ji Yushi replied, “Because at that time, I found your attitude really annoying.”

Song Qinglan laughed out loud, his chest shaking with the sound. “That’s true. I wonder how many black marks you put against me! Otherwise, how could you have kept it from me for so long?”

Ji Yushi wasn’t the type to enjoy keeping people guessing. If Song Qinglan had asked, he would have answered.

But the key was that Song Qinglan needed to ask.

“You told me everything important, except for this,” Song Qinglan said. “Why did you change your name completely?”

Ji Yushi said, “A name is just a label; it doesn’t really matter.”

Song Qinglan frowned.

Ji Yushi had said this before, and back then, Song Qinglan didn’t think much of it. But now, he sensed that this statement carried a deeper meaning.

As expected, Ji Yushi’s smile faded, and he asked, “Was that call from Minister Wang?”

Everything was as Ji Yushi had anticipated.

He hadn’t planned to keep his identity as “Han Han” a secret from Song Qinglan for long.

“Yes,” Song Qinglan replied. “If it weren’t for your mission report, I wouldn’t have known that you encountered your father in the Cube.”

Song Qinglan could almost imagine how Ji Yushi must have felt at that moment.

He could also picture the difficulty Ji Yushi had in responding with “Yes, it’s quite a coincidence” when Sheng Yun remarked, “What a coincidence, my son also has a similar game console,” knowing that the person who had given him that game console was standing right in front of him.

But there’s no such thing as truly understanding someone else’s feelings.

So Song Qinglan could never fully grasp what Ji Yushi was feeling at that time. Even the slightest taste of it left him with a bitter, uncomfortable sensation in his heart.

Father and son met in a time and space where the past and future were intertwined.

In that space, time didn’t follow a linear order. Just a simple word, a small reminder, could potentially alter their fate entirely.

Yet Ji Yushi had just sat there, watching his father leave, before turning to his teammates and saying, “Let’s go.”

“After we came back, I kept thinking about one question,” Ji Yushi said slowly. “Do you think he recognized me?”

Song Qinglan felt a sharp pain in his heart, as if something had tightly squeezed it, making it hard to breathe.

It was a cruel question.

How should he answer? He didn’t know. If he said yes, Sheng Yun would seem heartless. If he said no, Ji Yushi would be disappointed.

Because Song Qinglan knew that beneath Ji Yushi’s cool exterior was a heart as pure as a child’s. Having lost his father at a young age, no matter how old he was, he, like every other child in the world, yearned for his father’s love.

“Who would have thought that Han Han would grow up to be so good-looking?” Song Qinglan chose to answer like this, “Even I didn’t recognize you. He probably didn’t either; you’ve changed so much.”

Ji Yushi blinked. “Oh, so you were lying when you said I was especially good-looking as a kid.”

Song Qinglan chuckled.

He hadn’t expected Ji Yushi to joke so quickly.

Ji Yushi then returned to the previous topic, “As for why I changed my name…”

Song Qinglan asked, “Does it have something to do with your father’s ‘suicide’?”

Seeing Ji Yushi nod, Song Qinglan continued, “You mentioned running into the killer in the stairwell. It was an unsolved murder case, yet Sky Vault classified it as a ‘suicide’.”

There must be some intricate connections there.

Ji Yushi had never imagined that one day he would meet someone to whom he could reveal all his secrets. So, after collecting his thoughts, he prepared to tell Song Qinglan all the clues and mysteries he had pieced together over the years.

“The temporal displacement technology developed during those years was already quite mature. If they really wanted to solve the case, they could have quickly identified the killer, especially since my father was a key researcher within Sky Vault.” Ji Yushi explained, “But instead, the case was closed late, and I was subjected to endless questioning. My mother died in a car accident when I was very young, and after my father’s death, I had no legal guardian. A teacher wanted to protect me, so they arranged for my adoption, changed my name, and used legal means to completely shield me.”

He lost his father, and even his name.

Professor Ji told him that a name was just a label and didn’t matter.

In his heart, he was still Sheng Han, still that child.

But what Professor Ji didn’t anticipate was that the trauma led Ji Yushi to develop hyperthymesia. Even under a new identity, he never gave up his determination to uncover the truth. Over the years, as the key personnel involved in Sheng Yun’s case gradually changed, the obstacles to solving the case diminished. As an adult, Sheng Han successfully entered Sky Vault, and his outstanding abilities were recognized by the Recorders’ Department. With tacit approval from all levels, he began completing tasks to earn points.

Ji Yushi said, “I believe my father’s death is connected to this ‘all-era significance of Sky Vault’.”

Song Qinglan frowned. “He was part of the research team.”

It was rumored that the members of the research team either went mad or died. It seemed that this wasn’t just hearsay.

The Sky Vault project, with its all-era significance, was ultimately completed and put into use.

“It’s not just that,” Ji Yushi looked at him and said, “He also participated in designing the Cube.”

Song Qinglan’s expression changed, deeply shocked.

The Cube was unpredictable, and in a certain sense, it could truly bring together “all eras” at a single point. That’s how they encountered Lin Xinlan from a year ago, Zoe from decades later, and even Yuu Morita from different eras.

“He once gave me a souvenir from a conference—a real Rubik’s Cube,” Ji Yushi shared the dream he had inside the Cube, then continued, “I wasn’t sure about this, and I didn’t know the specifics of the Cube’s design, so I wasn’t sure how to solve it at first. Even after finding a solution, I wasn’t sure, until he appeared with his colleagues, confirming that he really had a hand in designing the Cube.”

Someone who wasn’t a Guardian but appeared in a time meant for Guardians to complete their tasks.

Skipping over the details of that moment, Ji Yushi asked Song Qinglan, “Don’t you think the Cube mission itself was very strange?”

Song Qinglan replied, “I’m all ears.”

Ji Yushi explained, “The previous Ouroboros and Chaos missions at least had a purpose. Whether it was to destroy a collapsing world or close a time rift, we knew why we were doing it, so there was a consistent logic throughout the mission. But the Cube mission…”

“Was pointless,” Song Qinglan interjected, “It looked grand and impressive, but after completing it, we didn’t even know why. All we knew was that the timeline was chaotic, and piecing it together marked the end of the mission.”

“You’re right.”

Ji Yushi nodded in agreement and then revealed his thought, “It was actually a half-finished product.”

“A half-finished product?”

“Yes.”

Ji Yushi said, “Or rather, it didn’t have a specific purpose because it was just a concept, an experiment.”

“They were experimenting to see if, by completely shattering the timeline, they could gather Guardians from different times at a single point, regardless of whether they were from the future or the past. It’s a grand concept—‘all eras existing simultaneously’.”

Time is inherently linear, with a sequence.

The process by which things change within this sequence is what we call time itself.

But what if time were like a body of water?

It has no beginning or end, no order, and it remains still, only rippling in response to changes, yet always maintaining its original state.

In a certain sense, people would be living in another dimension.

Song Qinglan felt a chill run down his spine, a deep sense of unease.

Ji Yushi felt much the same.

The vastness of the universe renders humans as insignificant as ants.

No matter how advanced human civilization becomes, it is not truly divine. Just hearing this concept is enough to instill fear.

Ji Yushi said, “I don’t know if it was because they realized that this research project defied the principles of nature, so they…”

At this point, he seemed to struggle to continue, his throat tightening, and he paused for a moment before managing to go on, “So they ultimately halted the project, and somewhere unknown to everyone, created ‘Sky Vault with significance across all eras,’ creating this mother system that is above the project, and also restricts its development.”

“So, this is the intelligent system you mentioned that day,” Song Qinglan said, pulling Ji Yushi into his arms and kissing his forehead, “the mother system responsible for maintaining stability.”

Past events are like a thick fog.

They are deeply entangled in it, and only by finding a breakthrough can they fully understand the truth.

That’s why Ji Yushi has to go back.

The two stayed in the library for a while longer before Ji Yushi asked, “Does this mean our vacation is over?”

Minister Wang’s call signaled the end of their holiday.

They were both aware of it.

“Yes,” Song Qinglan replied, “It was so short.”

Ji Yushi let out a soft sigh.

Song Qinglan smiled, “What, do you feel like you didn’t get to enjoy it enough?”

Ji Yushi responded with a quiet “Hmm” and rested his head on Song Qinglan’s shoulder, lost in thought.

Song Qinglan said, “But our mission rewards have been issued. After applying, we can return to work after claiming our rewards.”

Ji Yushi sat up.

He looked at Song Qinglan, as if waiting for him to reveal the final outcome.

“The Jiangcheng branch is very eager to have you,” Song Qinglan said. “Minister Wang called Minister Lin several times to poach you. So, she agreed to your initial request—to let you handle your personal matters before making a formal decision.”

“Really?” Ji Yushi wasn’t particularly excited. Song Qinglan had said so much without mentioning the key point, and Ji Yushi, being as sharp as he was, had already guessed part of it. “Did I fail the psychological evaluation?”

Song Qinglan replied, “Yes.”

Ji Yushi: “…”

“Why are you so disappointed? Don’t you still have me?” Song Qinglan smirked arrogantly. “I’ve accumulated two rewards, and after applying, I’ve been appointed as your temporary guardian. They’ve approved my request to take you back to that day.”

Ji Yushi was stunned. “You used both of your rewards? What if you want something else?”

Song Qinglan casually stood up, gathering the stack of books to hand over to the nearby robot. “Let’s go, Consultant Ji. I’ve booked a table at six. Let’s make the most of our last date. After dinner, we have to head back.”

Ji Yushi also stood up, seriously suggesting, “I can wait for the next evaluation. You don’t need to use both of your rewards.”

Song Qinglan said, “There’s only one reward I want.”

Ji Yushi asked, “What is it?”

“I’ve told you many times,” Song Qinglan said as he walked over, “I want you to stay.”