Magic Crystals
Siwoo left the night he had spent with Sera behind him and opened the convenience store the next day as usual.
When the quiet afternoon settled in, he left the warehouse door unlocked.
The moment it trembled, he locked the glass front door and stepped into the warehouse.
He opened the portal, and Liria was standing there.
A small pouch rested in her hand.
The instant she saw Siwoo, her expression dimmed just a little.
"Siwoo… I can smell another woman on you again. This time… is it someone from the real world?"
Siwoo did not deny it.
Liria let out a soft sigh and held the pouch out to him.
"Today I brought gold coins, and a few more of those refined crystals I mentioned last time."
Siwoo took the pouch and closed his hand over hers.
"Don't just leave. I want to be with you today."
Liria's eyes widened slightly.
Siwoo pulled out the otherworld outer garment he had hung in the corner of the warehouse ahead of time and slipped it on.
It was the simple robe-style cloak Liria had found for him before—plain enough that it did not look out of place.
When he draped it over his uniform, Liria smiled faintly.
"You'll stand out a little less now."
Siwoo took her hand and stepped through the door with her.
The air of the otherworld brushed across his face.
The two of them headed for Liria's house.
Once inside, Liria helped him out of the cloak and asked,
"Siwoo… would it be all right if I took quite a lot today? Convenience store goods. Salt and soap, pepper, cold drinks, and those strange paper-wrapped foods… I want to start making a little place for them on this side too. So you won't feel uncomfortable when you come and go."
Siwoo nodded.
"Take as much as you need. I'll restock later."
Liria brightened and slipped into his arms.
"Thank you."
They kissed as naturally as breathing.
As the kiss deepened, Liria slid her hands under his clothes.
Siwoo guided her toward the bed.
When Liria slipped out of her dress herself, her pale body was laid bare under the indoor light rather than moonlight.
Siwoo laid her down and slowly covered her with his own body.
Liria wrapped her fingers around him and whispered,
"Siwoo… put it inside me. Don't rush today… go slowly."
When he eased into her, Liria let out a thin moan and clutched his shoulders.
They held each other and moved slowly, deeply, bodies joining without hurry.
Liria buried her face against his back and rolled her hips to match his rhythm.
"Siwoo… it feels good… deeper…"
As climax drew near, she wound her arms around his neck and trembled.
Siwoo came with her, spilling deep inside.
They stayed locked together for a long while afterward.
Liria rested her forehead against his chest and spoke softly.
"Siwoo… I'll keep preparing things little by little on this side too. When you come, I want this place to feel at least a little like your home."
Siwoo stroked her silver hair and answered,
"Yeah. Let's take it slow."
They gathered their clothes, then filled the large bag Liria had prepared ahead of time with the goods he had brought from the convenience store.
Salt, pepper, soap, sports drinks, triangle kimbap, chocolate, wet wipes…
Liria smiled as she secured the bag.
"With this much, it should smell like you over here for a while."
Siwoo put the outer cloak back on and walked with her toward the door.
After they passed back through into the convenience store warehouse, he loaded even more goods for her to take.
Liria stood before the portal with the heavy bag and looked at him.
"Siwoo… next time I come, I can stay longer on that side, right?"
Siwoo nodded.
Liria gave him a brief kiss and vanished beyond the door.
Siwoo locked it, sat down behind the counter, and let out a long breath.
Liria was no longer simply someone who came to buy things.
Even in the otherworld, she was slowly building a space that belonged to the two of them.
And Siwoo himself no longer crossed over wearing only his convenience store uniform.
The afternoon of Gangnam's nightlife district drifted past the window.
Siwoo's real-world life had clearly changed since the door first appeared.
The biggest change was money.
Before, he had always been stretched thin just covering rent and living expenses.
Even a small dip in store sales left his pockets light, and hiring part-time help had been unthinkable.
Now it was different.
With the cash from exchanging gold and silver coins—and the otherworld goods Liria refined—piling up, the worry over monthly rent had long since vanished.
The cash hidden under his bed alone already exceeded three hundred million won, and it was only going to grow.
He was now in a position to aim for a 5.8-billion-won building; the very scale of his life had shifted.
His daily rhythm had changed too.
Before, he had worn himself out alone from morning until dawn, guarding the store.
Now, using the quiet afternoon hours to manage the warehouse door and receive the women from the otherworld had become part of his routine.
Lock the glass door, spend time with someone from the otherworld, lock the door again, and greet real-world customers—the rhythm had settled into his body.
His relationships had grown complicated as well.
In reality, Sera kept coming by regularly, and a new nightlife woman named Yuna had begun showing interest.
In the otherworld, Liria approached him with real feeling, while Seraphin made her desires blatantly clear.
Before he knew it, Siwoo had become the one who had to hold the center among four women.
Even his clothes had changed.
When he crossed to the otherworld, he wore the outer cloak Liria had found for him over his uniform.
In the real world too, he no longer dressed as carelessly as before.
With spare funds available, he had started spending a little on clothes and daily necessities.
Above all, Siwoo's gaze itself had shifted.
Before, his biggest worry had been how to cover that month's rent.
Now his mind was filled with how long he could keep the door open, how to gather 5.8 billion, and how to handle the women's feelings.
The convenience store was no longer just a means of survival.
It had become a secret hub linking two worlds—and a passage that could change his future.
Sitting at the counter and looking out the window, Siwoo often wondered how far these changes would go, and whether he could carry all of it to the end.
The neon of Gangnam's nightlife district shone as always, but the life Siwoo lived beneath it was already nothing like the life he had known before.
When the door first appeared, Siwoo had believed he could travel freely between the two worlds at no cost.
But as time passed, the things Liria and Seraphin said, and the fragmented information he picked up in the otherworld, began to form a single picture.
This door was not simply an open passage.
It had a maintenance cost.
One day Liria had carefully explained it to him.
"This door was born from a crack in mana. If you leave it alone, it slowly closes. To keep it open… you have to supply mana periodically."
Siwoo asked,
"How do you supply mana?"
Liria looked troubled.
"There are two ways. The first is to let the door absorb objects or crystals that hold mana. The second is… for a being who can handle mana to share their own power directly."
Seraphin put it more bluntly.
"Simply put, this isn't a free door you can keep using forever. You either offer magic crystals, or a dark elf like me or an elf like Liria has to pour mana into it regularly. Otherwise one day the door will start to fade and just disappear."
Only then did Siwoo understand why Liria sometimes stood in front of the door with her hand pressed to it.
She had been sharing a little of her own mana to stabilize it.
The problem was that the cost kept growing.
According to what Liria later told him, the mana needed to stabilize the door at first had been relatively small.
But the more people and goods that passed through, the more mana the door demanded.
Especially when large amounts of real-world goods crossed into the otherworld, or rare otherworld materials came into reality, the mana consumption spiked.
Siwoo ran the numbers in his head.
Right now Liria and Seraphin took turns replenishing the mana, but if he started moving even more goods for the building purchase, the two of them alone might not be enough.
In the end Siwoo found himself with a new worry.
To keep the door open, he would have to secure a steady supply of magic crystals, regularly pay beings from the otherworld who could handle mana, or find some other method specialized in maintaining the door.
The passage he had thought of as a free link between two worlds was turning into a secret facility with clear operating costs.
Siwoo stared at the door in the warehouse and muttered,
"In the end… nothing's free."
The night of Gangnam's nightlife district shone as always, but the price of the door hidden beneath it was growing sharper by the day.
On a quiet afternoon Siwoo left the warehouse door unlocked.
When it trembled, he locked the glass front door and opened the portal.
Seraphin stood there.
Today she was wearing the provocatively revealing outfit typical of otherworld dark elves.
Black leather and straps barely covered her body.
Seraphin looked him up and down and lifted one corner of her mouth.
"You're not going to turn me down today, right?"
Instead of answering, Siwoo let her inside.
The moment the door closed, Seraphin grabbed his collar and shoved him against the wall.
"I've waited long enough. Today we're doing this properly."
She pulled his pants down and wrapped her hand around him herself.
Confirming he was already responding, she gave a low laugh.
"Honest as always."
Seraphin dropped to her knees and took him into her mouth.
A dark elf's tongue was bold and quick.
She swallowed him deep, pulled back, and focused on the head.
Saliva ran down; Siwoo's hips twitched faintly.
After a while she stood, stripped off her leather pants and underwear herself.
Firm white thighs and already slick flesh came into view.
She turned her back to him, settled over his length, and slowly lowered her hips, taking him in.
"Haa… still so big…"
Seraphin moved roughly from the start.
She rocked her hips fast, occasionally sinking all the way down until she took him to the root.
When Siwoo gripped her waist and thrust up from below, she let out a thin moan.
"Harder… I hate it when it's gentle."
Siwoo drove his hips harder; Seraphin's moans grew louder.
The wet slap of skin and her low sounds filled the warehouse.
She twisted to look down at him over her shoulder.
Desire filled her lightly sweat-damp face.
"You don't do it like this with that silver-haired elf, do you?"
Instead of answering, Siwoo tightened his grip on her waist and picked up the pace.
Seraphin matched him and shuddered.
"Haaa…! Yes… just like that…!"
As climax neared, she grabbed his hands and forced them onto her breasts.
When Siwoo pinched and twisted her nipples hard, her insides clenched violently.
She came with a low, almost sobbing moan, and Siwoo, unable to hold back against that grip, poured himself deep inside her.
They stayed in that position for a moment, catching their breath.
Seraphin slowly rose and let him slip free.
Mixed fluids ran down her thighs.
She roughly straightened her clothes and looked back at him.
Her expression was satisfied.
"Not bad. Next time I'll ride on top more."
Instead of gold coins, Seraphin pulled out a small pouch and tossed it to him.
"I'll tell you something special today. You need magic crystals to keep the door going, right?"
Siwoo opened the pouch and found several small magic crystals inside.
Seraphin shrugged.
"They're not that hard to get. Some of the stuff in your convenience store sells for a fortune in the otherworld. Especially those cold drinks, the sweet snacks, and those weird paper-wrapped instant foods."
She ticked them off on her fingers one by one.
"Bring those over and nobles or mages will pay several gold coins for them. Prices jump even higher in summer and during festivals. You stock me with the goods, I sell them high in the otherworld and trade for magic crystals. We both win."
Siwoo asked,
"That easy?"
Seraphin laughed.
"Not easy. I still have to haul and sell them. But it's the most convenient way to get the magic crystals you want on a regular basis. Way faster than asking Liria."
She caught his collar once more and added in a low voice,
"Of course… the price will still have to be paid now and then, like today."
Seraphin did not dig any deeper.
She walked toward the door and glanced back.
"Next time stock up on drinks and snacks. I'll take care of the magic crystals."
She vanished beyond the portal. Siwoo locked the door and looked at the magic crystals in the pouch.
Selling convenience store goods at a premium in the otherworld to secure magic crystals.
The most realistic way to cover the door's maintenance cost had just appeared.
Siwoo sat at the counter and gave a short laugh.
"In the end… it all comes down to business."
The afternoon of Gangnam's nightlife district drifted past the window.