Chapter 3: The Currency of Causality

“Hmm, this space is still too cramped. No defenses either. What you need most right now is ‘Causality.’”
The bird inspected the shop like a picky tenant, muttering something incomprehensible.

“Causality…?”

“Yes! From now on, when other gods visit as customers, make sure to ask for ‘Causality’ as payment.”

“Got it. Causality, Causality.”
I repeated it to myself to not forget. But why?

“Doesn’t it feel stifling in such a small space? Causality can help with that.”

“As I mentioned before… I don’t understand this kind of stuff.”

“Oh, my apologies. It’s just so basic.”
The bird said it would show me and led me outside the shop.

“The land around this garden could use some expansion, don’t you think? You’ll want to plant more things in the future.”

“Well, sure, but I don’t have anything to plant right now…”
Expand the land? Before I could dwell on the question, the bird waved its wing toward the garden, and an astonishing change occurred.
Like assembling a puzzle, a patch of land about a meter square appeared in the air with a bright glow and attached itself to the garden’s edge.

“Whoa?”

“This is one of the things Causality can do.”

“You can expand the area?”
I stepped onto the new patch, marveling at the sensation.
This tiny, floating rock-island of a space had grown just from a single wave of the bird’s wing.

“Consider this a tip. For letting me taste that precious Silverwing Herb Tea, this is the least I can do.”
Who doesn’t love a tip? My fondness for the bird skyrocketed. What a kind creature.

“Think of Causality as a currency only gods can provide. You can use it to give this space ‘Legitimacy.’”

“Legitimacy…”

“Right now, this place is just a clump of memories drifting in the gaps of time.”

“Oh, you mean a place etched with memories?”

“Exactly!”
I thought of the notebook that had kept me company, giving me the illusion of reading during my endless time here.
That seemingly meaningless essay.
Now, my suspicions were confirmed.
This place was indeed the “place etched with memories” from the notebook.

“Good to know you’re catching on! As I said, this is just a bundle of memories, practically nonexistent. Hmm, think of the most vivid, beautiful memory in your mind.”

“I-woon, thank you, always.”
The bird’s words triggered a memory reflexively.
There was someone whose presence always brought joy. Most memories with them were beautiful.

“Now, is that memory real right now? Can you touch it? No matter how much time passes, can you always recall it in the same exact form?”

“…No.”
I shook my head, a bitter taste in my mouth.

“Maybe the memory I recall today will differ slightly from tomorrow’s. It might even grow fainter. The size, number, or color—everything could change, even a little.”
I’d been confident I could always remember that person clearly, but the details were fading.
What were they wearing that day? Was it white? Or… maybe light blue?

“It doesn’t wear down due to weather or time because it only exists in your mind, not in reality.”
The bird spread its wings wide, encompassing the ground we stood on.

“That’s the state of this place right now.”
A place built from memories.

“The difference is, unlike memories that exist only in your mind, this place is a refined intersection of countless memories, anchored in the gaps of time. So, if you use Causality to grant it Legitimacy, this place can finally ‘exist’ and embrace change.”

“Change… But I’ve been cleaning and fixing things here already.”

“That’s because you, arriving here, became a form of Causality yourself. But we can’t use you as material to expand the land, can we?”
Its words stirred an odd feeling, deepening my questions about my own existence.

“My first payment to you is three units of Causality. This is the maximum I can offer, aside from the tip earlier.”
The bird handed me something.

“Will you accept my offer?”

“Well, I see no reason to refuse, so I’ll gratefully accept.”
It was a lump of light.
It looked like glowing clay, kneaded into shape.
The coin-sized orb shimmered restlessly in my hand, on the verge of scattering yet holding together.
No form, yet tangible. No color, yet vividly visible.

“Now, you’re the master of that Causality. Use it as you wish.”
As I wish.
Seeing me struggle, the bird nudged me gently.

“Expanding the land seems like the first step, no? Or how about fixing that crumbling roof? Oh! I just noticed this shop has a second floor. I didn’t see stairs inside, though—maybe add some? A stylish streetlamp outside could add charm too.”
Chirping away, the Thunderbird seemed no different from a sparrow.

“I get it.”
So, I shouldn’t overthink it—just treat this like a shop management game. Like those mobile tycoon games that were once all the rage, running a café, restaurant, inn, or farm.
Causality is like currency, it said.
So, I can use it to expand the land or upgrade the shop.

I decided to follow the bird’s advice and start with the land.

“How do I use it? Like this?”
I mimicked the bird, extending my hand with the Causality toward the empty space by the garden.

Flutter.
One of the three glowing orbs flew from my hand toward the spot I pointed at.
The light reached the void, grew larger, and formed a patch of land about a meter square, seamlessly joining the edge.

Wow… I feel like a wizard.

“Are you using all of it to expand the land?”

“Hmm, the garden’s idle for now, so I’ll save the rest.”
Wasting it and running out when I needed it would be a disaster.
Didn’t the bird say only gods like it could produce Causality?
With no idea when the next customer would show up, I couldn’t squander it.

As I made up my mind, the remaining Causality orbs floated up from my hand, drifted to my chest, and were absorbed with a soft whoosh.

‘What’s that? A storage system?’
I rubbed my chest, feeling a faint unease despite no sensation.

“Pity.”
The bird glanced at the dilapidated roof with genuine regret.
It must really bother it.

“Now that I’ve paid with Causality, let’s discuss the second payment.”

“There’s more?”
Wasn’t Causality enough? It’s practically a game-changer for this space.

“You said your only menu is Silverwing Herb Tea, right? You need to develop new ones!”

“Oh… I thought you’d tell me to use Causality for that.”

“Ho-ho-ho.”
The bird let out a clear chirp, correcting me.

“I forgot to mention—life can’t be created with Causality. If it could, Silverwing Herb wouldn’t be extinct across dimensions.”
Fair point. A currency this powerful would be too much without limits.

Still, I was a bit disappointed I couldn’t pull off the classic tycoon game move of “hiring staff.”
Even a pet would’ve been nice. It’s too lonely here.

“So, here’s my proposal: I’d like to invite you as a guest to my dimension.”

“Your dimension…?”

“I’d love to have you open a café there and sell Silverwing Herb Tea forever, but…”
I instinctively furrowed my brow.

“Since you’re a resident of another dimension, you can’t settle in mine. You can only visit.”
The bird’s offer was this:
Go to its dimension to gather ingredients for new menu items.

“As a god, I can’t appear directly before residents. If a god’s existence is confirmed, the dimension falls into chaos. If everyone knew an omnipotent god existed, they’d rely on it for everything, right? I’ve heard some dimensions are on the brink of collapse from religious wars and inquisitions, all because of a god’s mistake. Tsk tsk.”
Since it couldn’t fetch ingredients itself, I’d have to do it.

“And I don’t have an eye for ingredients.”
I didn’t either, but the bird was convinced I could spot them, given how I’d grown Silverwing Herb from seeds I found.
It brushed off my protests that I’d just stumbled across them in a drawer.

“Just bring back one thing. Greed for more will only bring trouble.”
In other words, I’d be a dimension tourist, picking up an ingredient if I found one and returning.

I mulled over the Thunderbird’s second offer longer than the Causality one.
How do I know what its dimension is like? What if this bird loses me like my god did?

“I’d never make the same mistake as your dimension’s god. Safe travels! Guaranteed return!”
As if reading my thoughts, the bird boasted confidently.

“To attract your dimension’s god, you’ll need a variety of menu items. No need to hesitate. Accept my offer.”

‘Staying here alone would just be lonely and bleak. A trip to this “dimension” could be a nice change of pace. I’m curious about the place this bird manages.’
Even if I couldn’t identify ingredients, I could grab something that looked promising.
Anything that blooms or bears fruit could work, right?

“Ho-ho-ho, decided? Then hop on.”
The bird scurried to the edge of the land, lowered itself, and turned its back to me.

“…Hop on?”

“Don’t worry. I keep my feathers well-groomed, so the ride will be comfortable! Oh, hold my neck feathers tight—you might fall.”
I stared at the bird’s back, wondering if my decision was too hasty.

“Not getting on? I could grab your shoulders with my talons and fly, but that might make you queasy. And it’d hurt.”

“No, I’ll ride. Let me on!”
Imagining myself dangling from those massive talons like prey sent a chill down my spine.

I pushed aside my hesitation and carefully climbed onto the bird’s back. Its purple suit crumpled under me, but the bird didn’t seem to care.

“Here we go!”
There was no warning.
The moment I felt my body lift, an immense pressure hit, and a blinding light flooded my vision, too bright to keep my eyes open.

When I finally regained my senses… I was standing on unfamiliar ground.