Multiversal Manifestation System

As Wang Zi waited for Rengoku to sort out his thoughts, a million questions about his new ability buzzed in his mind. The ability to manifest himself into the worlds he created opened doors he'd never dreamed of, but it also presented logistical challenges he hadn't considered before.

He leaned back into a chair, staring at the system interface floating in his mind.

"Alright, System," he thought. "We've got to clear some things up. If I enter one of these worlds, where will the timeline start? Do I have to jump in at the beginning of the story, or can I choose any point I want?"

The system responded immediately, its mechanical voice devoid of emotion:

"The start of the timeline can be selected by the host. Specify the desired entry point when activating Reverse Manifestation."

"Good. That means I don't have to start from scratch if I don't want to." Wang Zi exhaled a breath of relief.

But more questions quickly bubbled up in his mind.

"And what about time? If I spend days or even weeks in one of these worlds, will I lose time here? Can I speed it up or slow it down? What happens if I need more time to make changes?"

The system paused briefly before responding:

"Time in the real world and the fictional world are synchronized. However, time in the fictional world can be sped up, without affecting the real world, by using System Points. Reversal of time is not permitted."

Wang Zi sat up straighter, his brows furrowed.

"So, no rewinding if I screw up," he muttered. "That's... fair, I guess. But speeding up time could be useful."

Hua'er appeared by his side, her white hair fluttering gently as she perched on the edge of his desk.

"Master," she began cautiously, "do you think this will cost a lot of SP? Speeding up an entire world's timeline sounds expensive."

"Probably. But you know what they say Hua'er, 'Time is money, friend'." Wang Zi chuckled.

He rested his chin on his hand, his mind spinning with possibilities.

"If time is synchronized and I can't reverse it, then I'll have to be careful about where and when I step in. If I start too early, I risk messing up the timeline too much. If I start too late, I might not have enough time to change things."

Hua'er nodded thoughtfully. "And if you speed up time, you'll have to manage your SP carefully. You're earning a lot now, but that could change depending on how your works are received."

"True. But I think this ability changes the game entirely. If I can influence these worlds, not just summon characters from them, then the potential is limitless. I could build alliances, create stronger techniques, even recruit entire factions to fight the Silent Ones."

He glanced toward the room where Rengoku was still watching Demon Slayer, the flickering light of the projector casting faint shadows on the walls.

"This also means," Wang Zi continued, "that if I go into Rengoku's world, I'll have to decide exactly when to start. Do I step in before his death and change everything? Or do I wait until the aftermath and help them rebuild?"

"Master, if you choose to step in before his death, won't that risk altering the events too much? The timeline might unravel in ways you can't predict." Hua'er tilted her head.

Wang Zi shrugged. "Maybe. But that's the point, isn't it? To make things better than they were. If I can stop the Hashira from dying, if I can keep their strength intact, then they'll be an even greater force to summon when the time comes."

"Didn't Shinobu have a sister that died? I remember it wasn't too far from the start of the plot. A good place to start, I have plenty of time to plan from there." Wang Zi kept thinking.

The system's answers left him with a lot to think about. The ability to speed up time was a double-edged sword - it could accelerate his plans, but it would also drain his SP quickly. And the inability to rewind time meant he'd have to plan every move carefully.

As he sat back, his gaze focused on the flickering interface in his mind.

"This is going to take a lot more strategy than I thought," he muttered.

The simulated light of the virtual room flickered softly as Rengoku sat on the holographic couch, staring at the paused image of the Demon Slayer anime projected before him.

Despite being in a virtual world, everything felt real, the warmth of the couch, the weight of his sword now resting at his side.

But Rengoku wasn't at ease. His fiery eyes, usually filled with determination, flickered with confusion and unease. He gripped his sword tightly, as if grounding himself in this strange new reality.

Wang Zi entered the room silently. He didn't say a word, instead moving to sit at a table near the couch. He leaned back in the chair, his arms folded, and simply watched Rengoku.

Several minutes passed in silence, the tension palpable. Finally, Rengoku turned toward Wang Zi, his fiery gaze meeting Wang Zi's calm yet unwavering stare.

"My days in that world are gone," Rengoku said, his deep voice breaking the silence. Though his tone was firm, it carried an undercurrent of vulnerability.

"But if what you say is true, and this universe faces the same dangers as my world did... then I will not let my flames die out. My mother's wishes, they still burn within me. I will continue to protect humanity here, just as I did there."

Wang Zi's face lit up with a wide grin, his joy impossible to contain. He stood abruptly, his chair scraping the floor as he stretched out his hand toward Rengoku.

"Welcome to the team, Rengoku Kyojuro. You're the first member."

Rengoku blinked, momentarily taken aback by the gesture, before his fiery smile returned.

He stood as well, gripping Wang Zi's hand firmly. Despite the simulated environment, the warmth of their handshake felt real, tangible, a bond forged through shared purpose.

Wang Zi chuckled as he placed his other hand on Rengoku's shoulder.

"From now on, you're my brother. We'll fight side by side. Together, we'll burn brighter than ever."

"Brother, huh?" he said lightly. "It has been some time since I've felt a bond like this. Thank you, Wang Zi. I will not let you down."

"I know you won't," Wang Zi replied with a grin. "You're Rengoku Kyojuro. If anyone stands by their words, it's you."

Rengoku's smile faltered slightly as he tilted his head, curiosity flickering in his fiery eyes.

"But tell me, Brother Wang Zi, how do we begin? How can I start helping this universe?"

Wang Zi's grin turned sly as he gestured for Rengoku to sit again. "That's the thing," he said.

"You can't start here just yet. First, you have to go back to your world."

Rengoku froze, his brows knitting together.

"Back to my world? But... how? I am already dead there. What would I do there?"

Wang Zi leaned forward, his expression softening.

"I'm glad you asked." Slowly, he closed his eyes, and when they opened again, the Rinnegan blazed in both of his irises, their eerie purple radiance filling the virtual room.

Rengoku's breath caught, his body stiffening as he instinctively placed a hand on his sword. The power emanating from Wang Zi was overwhelming, even in this simulated space.

"This," Wang Zi said, gesturing to his glowing eyes, "is the Rinnegan. It's a power that lets me do many things, but one of its most incredible abilities is this: I can bring people back to life."

Rengoku's fiery eyes widened, his grip on his sword loosening.

"Bring people back to life?" he whispered, his voice trembling with awe and disbelief.

"It's expensive," Wang Zi admitted, "but not impossible. And for members of my team, my future allies, I'll do whatever it takes to make sure they're happy. You're the first member, Rengoku. That means you're no exception."

"Wang Zi... Brother... do you mean it? Could you truly bring back those who have fallen?" Rengoku's smile suddenly turned much brighter. 

Wang Zi placed a firm hand on Rengoku's shoulder, his expression solemn.

"I do. Not just you, but your comrades, too. If we go back into your world, into your past, I can make changes. I can rewrite the story, keep you and the others alive, give your world a future where the flames never die out."

"I'll help you fix you world, end Muzan. This is the least I can do for you, to make sure you can leave with no regrets!" Wang Zi stared straight at Rengoku.

Rengoku looked up, his fiery gaze now filled with unwavering determination. "Then I'll fight with you, Brother Wang Zi. No matter where, no matter when, I'll be there."

"Good. Now, you'll be going back to your world soon. It costs quite a bit to keep you here. When the time comes, I'll be there, and together, we'll rewrite your story." Wang Zi said.

As the conversation between Wang Zi and Rengoku drew to a close, a faint shimmer began to surround Rengoku's form. The edges of his body flickered like the flame of a candle in the wind.

Rengoku looked down at his hands, realization dawning on him.

"It seems my time here is up," he said, his voice calm but tinged with regret.

"You probably won't remember me, but I'll be there. Trust me." Wang Zi smiled.

Rengoku smiled, his fiery eyes shining with a mixture of gratitude and determination. "Even if I don't remember this, I'll trust in you, Wang Zi. You've given me hope. Don't let the flames die out."

Wang Zi's Rinnegan just stared straight at Rengoku as he was fading, his smile never leaving his face.

"See you soon, Rengoku!"

As Rengoku faded away, Wang Zi logged off the virtual world, it was time to set his plans into motion.

Back in the real world, he leaned back in his chair, letting out a long exhale. The faint glow of his system interface hovered in the corner of his vision, but he ignored it for now, his thoughts turning to the future.

"Alright," he muttered to himself, standing and stretching his massive frame.

"First things first, the two Demon Slayer movies. If I want to keep the SP rolling, I need to finish them and get them out before the final stage of the tournament."

"The series has been doing great, but the movies will push it to the next level. After that..."

His mind shifted to his next project: Naruto.

"Demon Slayer was the warm-up," he mused, pacing the room. "Naruto is where the real SP farming begins. Once it gets going, it'll blow Demon Slayer out of the water. It's longer, and packed with fighting scenes, drama, growth... It'll appeal to a broader audience. Especially the younger ones."

"It'll take time to get started, but once it picks up steam, I'll have a steady stream of SP." Wang Zi clenched his fists, his determination surging. 

For now, there was no rush to fix Demon Slayer's world. Wang Zi wanted to build his strength and his resources first. Once the Rinnegan was fully powered, he would manifest himself into the Demon Slayer world and set his plans into motion.

"I'll shed this fat body after the tournament," he muttered, glancing at his reflection. His red hair, a remnant of his connection to Nagato, shimmered faintly in the light. He smirked at his appearance.

"Not bad, I guess. Yahiko vibes aren't the worst. System, show me my status." Wang Zi ordered.

Name: Wang Zi

Age: 18

Class: Artist

Rank: SSS (Compatibility: 100%)

Level: 15

System Points: 197,656,332

Talents:

[Inhuman Reflexes]: Reaction speed increased by 50 times.

[Ultra-Mind]: Grants perfect memory, enhanced comprehension, and control over the body

[Uzumaki Blood]: Increases the host's physical stats, with an emphasis on stamina.

[Elemental Affinity]: Able to control mana of the five basic elements.

Basic Stats (average human = 10):

Strength (STR): 118

Agility (AGI): 74

Stamina (STA): 116

Intelligence (INT): 138

Wisdom (WIS): 143

Luck (LCK): 20

Abilities:

Rinnegan (Partially Unlocked):

Paths:

Human Path: Extract and absorb souls and mana from others.

Preta Path: Absorb most mana-based attacks and abilities.

Asura Path: Form mechanized limbs and weapons for offense and defense.

Animal Path: Summon a wide variety of creatures to aid in battle.

Locked Paths:

Deva Path: Manipulate attractive and repulsive forces.

Naraka Path: Call upon the King of Hell.

Outer Path: Preside over life and death.

"Hmm. Almost 200m even after manifesting Rengoku. It seems people are starting to rewatch the competition, Mitsuri and Gyomei are making good waves, very nice. I'll try pumping the Rinnegan with 250m to see if its enough. Also raised strength and stamina a little, fighting seems to be the best way to fuse mana with myself."

"One step at a time," he told himself.

Turning back to his interface, he made a mental note to start finalizing the scripts for the Demon Slayer movies.

"First the tournament, then SP. Then the Rinnegan. Then... the team."

Wang Zi's grin returned as he envisioned the future, his team, made up of the greatest warriors from across worlds, standing beside him to face the Silent Ones.

And with that, he began to put his plans into motion.