"Curious, aren't you?" Rin Tohsaka leaned in with an enigmatic smile.

"Tch. Of course I want to know what's going on..." Lin Luo shot her a glare, imagining the tiny demon tail wagging behind her. Then he paused, frowning. "You're not hiding something from me, are you?"

"I'm not keeping anything back - just haven't said everything yet." Rin shrugged, only revealing more when Lin Luo impatiently prodded. "Actually, what we saw in that mirror was slightly different from what Shidou saw."

"How so?"

"Perspective," Rin explained. "First of all, Shidou witnessed this scene within her dream. But as for us, our initial viewpoint was already the 'Unknown's' perspective... Oh right, we named that shadowy figure 'Unknown'. However at the final moment in the footage, we saw Unknown from behind - clearly not Unknown's own perspective anymore, but rather like someone filming from behind him. Makes sense?"

"Hmm... You're right." Lin Luo nodded after a thoughtful pause.

"But when Shidou viewed this scene within her dream," Rin continued solemnly, "she couldn't see Unknown at all. To be precise - no matter where or when she looked, her viewpoint was always aligned with Unknown's. What do you make of that?"

"What?" Lin Luo froze, though the experience had somewhat conditioned him to such revelations. After a moment's contemplation he muttered, "You're saying... The final scene we saw was filmed by Shidou herself."

"Exactly!" Rin snapped her fingers in approval. "Shidou has watched this dream countless times. Though she could witness the destruction of infinite worlds at the end, for some reason she could never see who caused it. Even when she manifested her dreams into reality, we saw exactly what she did - until finally she used her transcendence ability to forcibly shift perspective just before the dream ended, capturing Unknown's silhouette."

Lin Luo suddenly understood. Seeing someone's back was simple - just stand behind them. But if you could never see it despite every effort... That meant one thing: yourself!

Yes. Without mirrors or reflective surfaces of any kind, no one could ever truly see their own back.

If Shidou couldn't see Unknown's back in her dreamscape, that meant... Shidou was Unknown. And Unknown was Shidou.

But...

"Shidou must be confused about all this," Lin Luo mused.

At his words Rin nodded knowingly. "According to her, she could only observe the scene without any emotional connection. She strongly denied the idea of being one with Unknown herself, insisting it felt more like possessing a body."

"Do you know who or what Unknown ultimately is?"

Rin shook her head, disappointment evident in her voice. "Of course we tried. When Shidou realized she might be Unknown herself, she hypnothesized into the dream countless times through self-suggestion. But no matter how far she pushed transcendence, all she could see was an indistinct silhouette - not even the gender is clear. And... after repeated use of transcendence ability, that very dream seems to have developed resistance. Now she can't even glimpse Unknown's back anymore."

"Transcendence ability blocked?"

"That appears to be it,"

"A being capable of destroying infinite worlds... A dream powerful enough to suppress transcendence ability... What a headache," Lin Luo slouched on the sofa, closing his eyes and sighing heavily.

After several minutes he opened them again to meet Rin's gaze. "Then what conclusions did you reach?" He already knew they must've discussed this extensively.

As expected, Rin said: "Through our speculation and analysis, we reached these conclusions... First of all, the Heart of Worlds in its original form wasn't just an object - it was either a person or some higher intelligence. It likely possessed the power to destroy infinite worlds before being defeated by something even stronger, transforming into the Heart of Worlds which then got sealed away.

"After countless years, someone found this Heart and set up the Divinity War. Somehow we became its hosts through fate's design. As our hosts begin unraveling secrets about the Heart, fragments of what it once did start emerging - like in our dreams."

"What do you think?" Rin asked expectantly after finishing.

"...," Lin Luo stared blankly before finally saying, "That speculation is impressive."

"As expected - this was all our speculation. What's your take?"

Lin Luo pondered for a moment then said bluntly, "Essentially aligns with your theory given current information - it seems most reasonable. Though there are still many unsolvable problems... First of all, the Heart of Worlds has forty-nine pieces. If each possesses Unknown-level power, that would mean at least four dozen beings stronger than Yao. Second, what kind of monster could possibly subdue and seal such a powerful Heart? Third, if it's so strong, why would anyone risk placing it in Divinity War knowing it might awaken again?"

"So while our theories seem similar on surface level, they still feel unrealistic... Basically we lack enough information."

"No," Rin shook her head. "We have one more crucial piece of evidence."

"What is it?" Lin Luo asked.

Rin smiled faintly before answering: "The Fourth Holy Grail War - Shidou's transformation. Don't you remember that?"

"Er..." Lin Luo suddenly froze. How could he forget? At that time, Shidou had transformed into someone completely different - powerful and extreme, her original kindness gone entirely replaced by absolute 'good' pursued at any cost.

Lin Luo had every reason to believe she would have obliterated the Type-Moon world if they hadn't pulled her back in time. Because... where there are people, there's no such thing as absolute goodness.

The extreme Shidou from then and the Unknown who destroyed infinite worlds began overlapping ominously in his mind...

If that was truly what it meant, this situation would be extremely dangerous!

Lin Luo felt a chill run down his spine.

"So while our theories stem purely from speculation," Rin concluded, "we believe they're at least pointing us in the right direction. The Heart of Worlds... possesses its own personality separate from ours!"

"What are you planning to do about it?" Lin Luo asked.

"Need I say? Of course we'll uncover all the secrets." Rin answered without hesitation.

Lin Luo looked at her face - no doubt, no uncertainty, just a decision already made and solidified in stone.

"Is that really wise?" Though he knew he couldn't stop them now, Lin Luo still couldn't help but ask, "If the Heart of Worlds truly possesses its own personality, your efforts might end up serving it. One day, that personality could completely replace yours... Is that really what you want?"

"We're aware of this possibility," Rin said solemnly, "Anyone who witnessed Shidou's transformation can't guarantee they won't become like that themselves one day. But!" She looked deeply into Lin Luo's eyes and declared firmly, "No one knows what the future holds. If we don't strive forward out of fear being replaced by others, we'll never be able to protect anything important. At least for now, to safeguard everything we have and ensure our descendants can live in peace, we must move forward - we need the power of the Heart!"

"..." Lin Luo could indeed acknowledge this. The Heart's power was necessary - after all, the Proxy Gods' schemes had not yet been fully destroyed, seven Hearts were already in their hands waiting to be transformed into Unknown-level strength. Even Yao would face certain death if they did that. And they couldn't stay under Yao's protection forever.

Clearly, upon initial discovery of Heart secrets, Rin and others must have realized this possibility too - hence their desperate pursuit for the Heart's power, despite its potential cost...

Lin Luo couldn't stop them, nor did he have right to. The struggle to gain strength while protecting important people... wasn't that exactly what he was doing himself?

Regarding this heavy topic, neither continued discussing further, choosing wisely to let silence linger until Lin Luo finally spoke again after some time: "By the way, I've been meaning to ask - what's up with Reian?"

"What else could it be? She's your daughter, are you trying to deny fatherhood?" At this, Rin instantly changed her expression, glaring at him with displeasure.

"I didn't mean that," Lin Luo groaned, "I'm asking when exactly were you planning to have a child? Why wasn't I told anything during my previous visits?"

"Wanna know?" Rin sipped tea while sidelong glancing at him.

"Of course."

Rin nodded and gently set down her teacup before saying four words: "That's a secret."

"What the..." Lin Luo was speechless, "I at least deserve to be informed, isn't that a bit too much?"

"You only have parental rights," Rin said coldly.

"That sounds unfair,"

"Wanna fairness? Then let me ask you something - what about Boroboro Mingong?"

"This is..." Lin Luo's tone faltered instantly as his confidence waned. He had known this would happen eventually when an illegitimate daughter came out into the open, bringing with it all those complicated stories. With no way to avoid it now, he changed topic hastily: "Ah yes, today's weather is nice. Shall we go somewhere together?"

Probably due to their exposure to Heart secrets or perhaps because they had lived too long in other worlds and witnessed so many things that drastically altered their worldviews, Rin remained somewhat tsundere but no longer interfered with Lin Luo's private life if he didn't mention it himself.

Soon after, the two truly set aside all other matters like normal people would do, enjoying themselves for a whole day. That night they slept together naturally, indulging in passionate lovemaking until exhaustion overtook them.

And while Rin was emotionally overwhelmed from their intimate moments, Lin Luo skillfully used sweet words to finally pry out information about Reian. Though this wasn't exactly something to celebrate - at least not for mother and daughter. The circumstances surrounding Reian's birth were truly filled with hardships.

Reian hadn't been born on Sky City but in another world, an advanced level where even Rin's strength couldn't guarantee free movement at the time. Compared to Mingong, Reian received almost no care after her birth yet had to endure relentless hunts from ancient monsters and crossworld creatures - a death-defying survival that bordered on miraculous.

Yet perhaps this was fortunate. In that highly mysterious world, due to multiple brushes with death, Reian's potential emerged early with many incredible abilities emerging... such as instant memory, magic absorption, essence materialization, even future vision etc.

Often she survived only through these miraculous capabilities.

However because of her extremely young age at the time, she couldn't control any of them. Previous outbursts left aftereffects so Rin had sealed all Reian's powers upon returning to Sky City, waiting for her to grow older before resolving those abilities...

The next morning, Rin decided to return to another dimension. Before leaving, she entrusted Reian into Lin Luo's care with serious instructions: "Take good care of her these ten days."

Lin Luo would stay in Sky City only ten days before heading to Type-Moon World - along with Rin and some others from that world as previously arranged.

Originally, Rin could have simply rested on Sky City for those ten days before proceeding to Type-Moon World. But knowing what was important, she chose otherwise. Ten days of rest meant falling far behind in Heart-of-Worlds exploration compared to others - something unacceptable in her eyes.

No one knew when Proxy Gods would launch their full-scale attack or how strong they'd become upon doing so. Not wanting to regret future actions and grasping the desired future firmly, they had no choice but to keep advancing relentlessly forward, becoming stronger every day.

They also hoped that in potential battles ahead, they wouldn't be the ones needing protection.

Thus for strength's sake, they wished not to waste time.

Understanding her reasoning, Lin Luo didn't stop her. Upon receiving Reian he nodded with a smile: "Safe travels."

"Bye Mama!" Reian waved goodbye with little hands.

Rin smiled faintly before entering another dimension without looking back.

As for Lin Luo, after glancing at the child in his arms, he smiled and said: "Reian, today Papa will play with you. What would you like to do?"

Since learning about this child's situation from Rin last night, he realized how much he owed her. At least these ten days, he decided to properly fulfill a father's duties.

Perhaps that was also why Rin entrusted the child into his care...

Though initially meeting Reian seemed rather shy, after actual interaction, Lin Luo quickly discovered she wasn't actually timid at all - quite the opposite in fact. She could be described as fearless of anything and everything... which made perfect sense given her early experiences witnessing countless fierce beasts while repeatedly caught in dangerous situations from birth itself.

So why had she acted so yesterday? Lin Luo pondered for a long time before concluding only one possibility: "This child is a sly fox."

Now being held by Lin Luo, Reian behaved perfectly obediently without crying or making trouble. When asked what game she wanted to play, after thinking slightly with her head tilted sideways, she answered: "Mahjong."

"Huh? Mahjong?" Lin Luo doubted he had heard correctly.

"Mm-hmm, mahjong," Reian nodded earnestly.

"Why do you want to play mahjong?" Lin Luo was puzzled. Though Sky City wasn't short of games like mahjong, it didn't make sense for a one-year-old child to be playing something like that - wouldn't toys like rocking horses be more appropriate?

"Because it's fun." Reian answered, then immediately tugged on his hair and insisted she wanted to play mahjong.

"Alright then. Mahjong it is," Lin Luo had no reason to refuse this strange yet reasonable request. Soon after he took Reian up to the twelfth floor of Sky City - this level served as entertainment center with all games available, including naturally enough... mahjong.

But just when they sat down at the table, Lin Luo immediately noticed a serious problem... Mahjong required four players. Though it was technically possible for two people to play, the fun factor diminished significantly - playing two-player mahjong would be extremely awkward indeed.

With this in mind, Lin Luo began looking around for someone else.

Sky City not only had three hundred mechanical maids but also relatives of hosts who came from other worlds. In their spare time these people often gathered at entertainment center as well, especially the maids who were regulars here once their work was done.

Sure enough, soon he spotted two figures in maid outfits nearby and immediately called out: "Hey you two! You've come just in time - we need someone to join us. Oh right, aren't your names Miyae Sakiko and Haruka Hara? Come over here and play mahjong with us!"

The two maids were instantly flattered by Lin Luo's invitation and hurriedly approached.

"Be careful now," the moment they sat down Lin Luo couldn't help but boast about his skills. "My mahjong skills are quite formidable - once known online as Sky King for my dominance, so don't let me 'fly' you away!"

As play began, not much could be said about Miyae Sakiko and Haruka Hara since they played regularly here and their game was straightforward... Mainly Reian was problematic. At just one year old, she had to lean forward on the table just to reach for tiles, playing completely without strategy - a complete beginner.

Well, this was normal considering her age. I'll have to go easy on her a bit... Lin Luo thought to himself.

One hour later...

"Are you guys cheating?!" Lin Luo jumped up with restrained urge to smash the mahjong table. After three games within an hour, not only did he fail to win any of them, he ended each game in negative points - getting 'flown away' by all three opponents! More surprisingly it was done in rotation by all three players.

Miyae Sakiko and Haruka Hara... Well, their original forms were at least Mountain King and Humanoid Computer - having such skills wasn't strange. But what about Reian? How could he lose to a child?! Years of mahjong experience were wasted!

"We're not cheating," Miyae and Haruka looked genuinely hurt.

"Hehe, Papa is so bad." Reian clapped her little hands joyfully.

"Fine then, let's continue! This time I'm going all out!" With no choice but to sit again, Lin Luo decided he wouldn't hold back this time.

In the end it took four people half a day of intense mahjong battle until midday mealtime arrived before they finally concluded their game.

"Playing mahjong is so much fun," Yuan Ban Lian smiled happily at the moment it ended.

"Yes, it's been great fun," Miyashiro Sak and Genzai Kazu were also smiling broadly.

Meanwhile in another corner of the room, Lin Luo had already become a gray background. After playing several rounds of mahjong all morning - dozens of games where every outcome was depressingly similar (he'd either be knocked out by this one or that), he felt like an ATM for those three... Dammit, being toyed with really wasn't fun at all!

"Dad, I'm hungry," Yuan Ban Lian jumped off her seat and wobbled over to Lin Luo, tugging his sleeve with a pouty expression.

Watching the girl who had just dominated him mercilessly now act as if she were the victim, Lin Luo felt an ache in his chest. Reluctantly he lifted her up onto his shoulders. "Okay, let's go eat... By the way, you drank quite a bit of milk earlier. Don't pee on me."

"Alright," she replied obediently.

Three minutes later as they descended to the ground floor restaurant, Lin Luo suddenly felt an ominous soaking sensation at his neck - immediately tears welled in his eyes.

"Dad... I peed," Yuan Ban Lian whispered timidly.

"...I understand," he said with a heavy sigh.

Five minutes later after changing into clean clothes and sitting down to eat, Lin Luo noticed Yuan Ban Lian feeding herself quite competently without needing help. He let out a relieved breath at last.

After lunch - when normal children would take naps around this time - Yuan Ban Lian remained as energetic as if she could slay a tiger single-handedly.

"Dad... More mahjong?" After briefly resting on the sofa, she crawled over to him and tugged his arm.

"...No more," Lin Luo chuckled nervously, having been thoroughly dominated for most of the morning and not wanting further humiliation.

"Then what else can we play?"

"Hmm..." Lin Luo pondered, then suddenly said, "The two kids who usually come with you didn't show up today."

"Who?"

"The ones who played with you yesterday," he explained.

"Oh," she responded before asking again, "What game?"

Play this and that - all you care about is playing! Even when your best friends aren't here to keep you company... Lin Luo silently muttered these thoughts but knew lecturing a child would be pointless.

"Want to play arcade games?" After some consideration, he decided on something within his expertise where he could reclaim the fatherly dignity lost during those mahjong sessions.

"Yes!" Yuan Ban Lian nodded eagerly.

With her securely cradled in his arms (having learned his lesson about letting her ride his shoulders), Lin Luo carried her to the 12th floor arcade and selected a fighting game machine.

Yuan Ban Lian wasn't playing for the first time - after starting the game she pressed buttons with surprising familiarity, though this mainly meant knowing their basic functions rather than mastering complex techniques like Lin Luo could do.

Yet despite her clumsy button-mashing motions, her in-game power was frighteningly formidable. Especially when two big "KO" displays appeared on screen, leaving Lin Luo completely stunned - he had actually been defeated by a one-year-old girl in his most specialized area of gaming? This wasn't scientific!

Lin Luo couldn't believe it. Yuan Ban Lian's button-pressing resembled random childlike thumping, yet this chaotic style still managed to defeat him? It must be because I haven't played for so long and my skills have grown rusty.

With that self-reassurance, the second round began. One minute later, his character was already lying dead on screen.

After winning twice consecutively, Yuan Ban Lian's innocent smile lit up as she said, "So much fun!"

This has to be cheating! Lin Luo stared at her in utter disbelief. Yet he knew the game system couldn't possibly have built-in hacks - even if it did, those would just manifest through player actions. But was Yuan Ban Lian actually using hacks?

Lin Luo felt as though his own reaction speed must be the real hacked element. Still, why was he losing?

Trying to figure this out, Lin Luo played more intensely while carefully observing her movements... After thirty minutes of effort, he gave up - Yuan Ban Lian truly defeated him through that random button-mashing style.

The following hours brought...

Racing games: Complete loss

Airplane simulators: Total defeat

Competitive matches: Crushed again

Sports games: Another resounding failure

...For an entire day Lin Luo suffered consecutive losses. Still, he never discovered why he lost - perhaps it just proved the old saying: The waves of the Yangtze River push forward constantly; those who fall behind are left stranded on the beach.

Totally shattered, Lin Luo didn't even want to touch a game controller again. Yet compared to his despondent state, Yuan Ban Lian continued playing joyfully - even after dinner and bedtime she still excitedly clung to him asking, "Dad, what else can we play?"

"Nothing more now, time for sleep."

"Waaaaah..." Yuan Ban Lian pouted with obvious disappointment.

However her disappointment didn't last long due to limited childhood stamina. When overwhelming drowsiness finally overtook her, she soon lay fast asleep on his chest.

Seeing her peacefully sleeping form, Lin Luo let out a final sigh of relief. "I hope she doesn't wet the bed," he prayed this unrealistic wish before closing his eyes for sleep.

The next morning as expected... The bed was soaked like Mount had flooded right there in their room.

Looking at that large puddle on the bedding, Lin Luo finally understood - taking care of children really was an incredibly complex task.

For several subsequent days Lin Luo repeated this painful routine. With increasing time spent together he gradually discovered some "hidden secrets" about Yuan Ban Lian.

Like one morning when maids were preparing breakfast, she stealthily entered the kitchen and replaced all the salt with sugar while staff weren't looking - unaware cooks then made a bizarrely sweet-and-sour meal.

Or during small Saber's naps, Yuan Ban Lian would silently approach her bed, tuck the tiny girl into a black box locked shut, vigorously shaking it until waking up Saber who'd panic-cry out "Who turned off the lights?!"

Also when maids were bathing in the bathhouse, Yuan Ban Lian would sneak outside and steal all their clothes away. Soon after this would inevitably lead to dramatic scenes of weeping maids running around naked while screaming.

There were many other similar pranks - daily incidents that didn't cause major damage but still created chaos.

Summary: Yuan Ban Lian was indeed a very mischievous, scheming child.

Lin Luo felt he couldn't let this continue anymore - at such a young age already showing bad behavior... What would happen when she grew up? To stop her antics, he reported everything he had seen to the three head maids.

However his righteous act of exposing family secrets didn't earn admiration but rather mockery, especially from Wei who decisively said, "Master, don't be ridiculous - the princess is clearly very well-behaved and would never commit such misdeeds."

"But I saw it with my own eyes!" Lin Luo insisted earnestly.

Yet more he explained, less they believed him. Gradually this turned into accusations that his jealousy over Yuan Ban Lian's popularity made him make up stories to report her for no reason.

Faced with these unreasonable claims, Lin Luo finally lost patience and took the three maids as well as himself into invisibility mode, following Yuan Ban Lian stealthily for an hour until witnessing firsthand when she stole all bathhouse clothes.

When they saw this, the three head maids stared in shock but instead of believing him... They immediately accused Lin Luo: "Master, you're truly evil - to make us believe your words you controlled your own daughter's actions! We were so wrong about you!"

The maids then continued condemning his monstrous behavior while defending Yuan Ban Lian.

Lin Luo stood there speechless.

Naturally, all recent pranks at Sky City inevitably ended up being blamed on him.

Second summary: While Yuan Ban Lian was mischievous and scheming, in everyone's eyes she remained the world's sweetest, most obedient good child.

Regarding this conclusion, Lin Luo felt utterly hopeless.

He didn't know how to describe this feeling - it was truly a sad reality when all others were drunk but you alone could see clearly.

Thus Yuan Ban Lian continued ruling Sky City with her mischief while he remained the fall guy for her crimes.

The most tragic part? Even though facing such an "extremely wicked" criminal, he couldn't hit or scold her - instead always had to coddle her. Because if she became upset and cried even slightly, this would immediately attract crowds of onlookers who'd demand explanations about why you made the child sad for any reason at all.

For a long time Lin Luo carried everything that Tohsaka and the world had once borne in their lives.

However fortunately, these tragic experiences eased somewhat by day six when two little dragon princesses Linglong and Dingdang finally returned to Sky City.

These girls had always shared good relations with Yuan Ban Lian - after all they were age-appropriate playmates who weren't strange at all, especially since Sky City lacked children entirely. For this precious companion, Yuan Ban Lian rarely targeted them with her mischief so their coexistence remained peaceful.

Earlier these two little dragon princesses had been temporarily forbidden from playing together due to family examinations - when Lin Luo saw them reappear that day he felt like divine beings had descended, nearly embracing and kissing them repeatedly.

Yet finally he suppressed this impulse for fear of scaring the girls away forever.

While these two couldn't stay overnight in Sky City due to dragon clan regulations requiring return home at night (so Lin Luo wasn't completely free from his troubles), during daytime they could always play together, while Yuan Ban Lian's nightly mischief energy was naturally less vigorous than daytime so things were relatively easier for him.

Most delighted of all that day was when Ming Meng arrived via teleportation in the evening. Probably due to shared scheming tendencies, this girl and Yuan Ban Lian instantly became inseparable - at least that was how they bonded... Though actually it wasn't quite "instant love"... That phrase seemed incorrect too!

Regardless, their mutual understanding between fellow schemers quickly reached a point where Ming Meng actively proposed wanting to sleep with Yuan Ban Lian from now on.

Though Lin Luo worried these two scheming children together might spread their sinister influence across all of Sky City, at least currently this would be beneficial for him - during both day and night he could finally escape Yuan Ban Lian's formidable presence.

Therefore Lin Luo readily approved the arrangement.

That night Lin Luo enjoyed his first truly restful sleep in a long time.

On day seven morning, after watching Ming Meng, Yuan Ban Lian and the two dragon princesses hold hands and run off together as expected, surprisingly Y appeared.

"What's going on? You look somewhat exhausted - menopause coming?" Lin Luo observed Y's weary appearance, perhaps due to his improved mood forgetting exactly who he was talking to while immediately activating his teasing mode.

Y sat down across from him with an enigmatic expression.

"W... What is it?" Lin Luo finally recalled her identity and felt some discomfort under her gaze.

Luckily Y seemed uninterested in causing trouble. She snatched the cup of tea Lin Luo had just sipped from, drank it all at once while propping up her legs with a lazy gesture and said, "Truly remarkable - you noticed my face showed exhaustion! Should I commend your progress as 'one should look at others anew after three days'?"

Lin Luo wasn't sure if this was praise or sarcasm. Instead of focusing on that line he glanced at the now-empty teacup on the table and thought to himself: Does this count as an indirect kiss?