In this post-apocalyptic world, I unexpectedly became a star galaxy master.

Hongtang was in a daze.

She remembered hearing some sounds before she fainted that night, and she did say something casually, something like "Tie your sister up."

[What? You mean you want this system to bind to your sister? No, once the system binds, unless you die, you don't have the authority to unbind.]

[However, I can voluntarily unbind myself from you before you become a Level 3 dimensional merchant. But rest assured, you are the best host I have chosen, and I will not unbind myself from you.]

Hongtang, “…”. We’ve just met, we don’t know each other well, shouldn’t we reconsider?

Hongtang felt little joy or anticipation towards this suddenly appearing system; instead, she was filled with wariness and confusion. She didn't know why the system had suddenly appeared, what it required her to do, or what price she would have to pay.

She doesn't believe in free lunches and disdains taking advantage of others.

But now that humans can live in outer space, it's not surprising that such high-tech things as systems exist. So she's still quite calm.

However, the most important thing right now was to find out what this system was all about. So she calmed herself down, sat back down in her chair, and prepared to start trying to get information out of the system.

"younger sister."

[What? Are you looking for your sister? The system has not detected a second living being in your room. Please confirm your request.]

“I didn’t ask you to find a younger sister. Didn’t you just ask me to name you? From now on, your name will be ‘Younger Sister’.”

【Uh, host, the system doesn't have a gender. It's neither a sister, brother, nor sister.】

Hongtang was amused by the system's serious, mechanical voice, and chuckled, "Hehe. Isn't it great to have a little sister? A little sister is a warm and comforting daughter. Calling her that makes our relationship seem very close, doesn't it?"

[Since the host likes it, then from now on my name will be "Little Sister".]

System: Although this name sounds a bit strange, as long as the host is happy.

[Ding, the system has completed the name change. Is there anything you need your sister to do?]

"Sister, please give a comprehensive introduction to this interdimensional trading system, including but not limited to: where you come from, what functions you have, the interdimensional merchant ranking system, the rights, responsibilities and obligations of the host, etc."

[Alright, I'll now begin the detailed explanation for you, host. The Interdimensional Trading System is activated by the strongest being in the current interdimensional plane, which is an interstellar plane. Interdimensional levels are divided from highest to lowest: Seventh Interstellar Civilization to First Interstellar Civilization. The current planet's interstellar level is... uh, tentatively set as a beginner interstellar civilization, that is, a first-level interstellar civilization, belonging to an ancient indigenous planet.]

At this point, the younger sister hesitated to speak. This planet's level was far too low, not even within the interstellar hierarchy. However, considering they were about to have a colony planet, it could be considered an early form of interstellar civilization, but it could only be classified as the lowest level.

[Each interstellar civilization can have a maximum of two interplane trading systems. Currently, the host's interstellar civilization only has one interplane trading system. The total number of trading systems in the host's interstellar plane is... uh, I don't have permission to view that yet.]

*注：1星际≥2星系，1星系=（1000万~200万亿颗恒星）

The dimensional trading system helps the host conduct transactions with merchants from various dimensions. Currently, the number of dimensions available for trading is zero.

The host bound to the system is called a dimensional merchant, with levels ranging from one to ten. Levels are increased through the number of transactions. Dimensional merchants can only trade with those of the same or lower level. The initial level is level one. Goods are traded using dimensional currency, with merchants setting their own prices and enjoying free buying and selling.

Level 1 Merchant: 100 transactions; Level 2 Merchant: 1000 transactions;

Level 3 Merchant: 1 transactions; Level 4 Merchant: 10 transactions.

Level 5 Merchant: 100 million transactions; Level 6 Merchant: 500 million transactions;

Level 7 Merchant: 1000 million transactions; Level 8 Merchant: 3000 million transactions;

Level 9 merchant: 5000 million transactions; Level 10 merchant: 1 million transactions.

[When trading with interdimensional merchants, the host should be careful to avoid receiving negative reviews. A negative review will result in the trading system being forcibly blocked for 15 days. If the host has any ongoing transactions, it will affect the delivery or receipt of goods.]

[The host's main task is to participate in as many transactions as possible to increase their merchant level. The system will upgrade every three levels the host gains. If the host becomes a level ten interdimensional merchant, the system will undergo a full upgrade. Each transaction or upgrade may generate a random reward.]

Hongtang, “…” To become a Level 10 dimensional merchant, one needs to complete 100 million transactions.

That's great, thank you for thinking so highly of me!

[The younger sister's role is similar to a trading assistant; besides helping the host with transactions, she can also perform energy scanning and disaster prediction.]

......

[Additionally, to unlock more permissions and access more information, the host needs to engage in more transactions and continuously upgrade their interdimensional merchant level. This will allow the younger sister to level up as well and better serve the host.]

While tidying up the study, Hongtang listened to the system ramble on for half an hour, finally understanding its purpose. It was simply a trading platform, posing no harm or mandatory tasks to the host.

That's good, Hongtang is very satisfied.

"Little sister, what are energy scanning and disaster prediction?" Hongtang asked as she put the old silver necklace her mother had left behind into a jewelry box.

At the same time, I felt a little strange. Was I seeing things? Where did the red and green patterns on that fingernail-shaped chip go? Now all that was left was an ice-blue line and a circle of 24 stars.

But her sister didn't give her time to confirm further.

[Host, energy scanning refers to my sister's ability to scan within a certain range to discover potential or hidden entities containing energy and obtain their data, which is then fed back to you. Since you haven't yet initiated trading, my sister's scanning range is 1 meter. After you initiate trading, her merchant level will be level one, with a scanning range of 10 meters. At the maximum level of one, the scanning range will be 100 meters. At level two, the scanning range will be 200 meters. With each subsequent level increase, the scanning range will increase by 100 meters. The highest merchant level, level ten, will have a scanning range of 1000 meters.]

[As for what constitutes energy, I can first scan the host so the host can experience it.]

“Okay.” Although she didn’t know what energy was, Hongtang’s intuition told her that this function was quite good. She decided to give it a try.

[Beep, the sister has begun scanning the host.]

[Beep, detected that the host's soul is bound to 1 spatial item... Beep, correction, 1 infinite spatial item... Beep beep beep, correction again, 1 super infinite spatial item!]

The sister's originally cold, mechanical voice was now trembling with excitement.

It never expected that it would encounter such a precious and rare spatial artifact on this primitive and backward ancient indigenous planet.

Even in the seventh interstellar civilization where it was born, very few people possessed it.