Crown Prince Sells Medicine
Chapter 8

[You have acquired the unprecedented ‘Mana Circle Slot’ in history.]

A message illuminated Raciel’s field of view, akin to a radiant beam of light.

It marked a pivotal moment, signifying the successful outcome of a perilous wager. Simultaneously, it conveyed a victorious message, reporting the acquisition of an unforeseen, substantial reward.

‘Mana Circle Slot? What on earth is that?’

Raciel kept an eye on the following messages.

[Your Mana Circle has acquired a kind of empty space, a void, in the process of forcibly tearing and expanding according to the user’s will.]

[This void has evolved into a storage space, a slot, that can contain matter and mana.]

[You will equip one slot in one circle.]

[The storage space of the slot expands as the level of the circle increases.]

[‘Slot 1’ has been opened.]

[Slot 1 is empty.]

[Slot 1 maximum capacity: 10 liters]

[Slot 1 current storage capacity: 0 liters]

“…….”

Reading the message, Raciel tilted his head.

Storage space?

Slot?

But the capacity is 10 liters?

‘It’s like a game inventory or item slot.’

He recollected some of the games he played on occasion. Drawing from his experience with game inventories, he made an estimated conjecture regarding the meaning of the message.

‘So, an inventory was literally created in my circle?’

It seemed so when he thought about it.

By eating something, he now had a space that could store a whopping 10 liters. As he thought about it, various ways to utilize it flooded his mind.

‘This might be…’

He wasn’t sure if he had obtained a more incredible potential than he initially thought. For example, within the slot of this Mana Circle…

At that moment…

“Um, Your Highness?”

Raciel’s ears caught a trembling, apprehensive voice. Tracing the source of the sound, he pivoted his head in that direction.

There stood Gardin, on the verge of tears.

Perplexed about whether everything was alright or if something had gone awry, his countenance and eyes resembled those of an individual who had just dropped their freshly acquired and activated smartphone on a tile floor.

In response, Raciel offered a faint smile, reassuring him that the smartphone was secure(?).

“Yes, what is it?”

“Um, are you alright?”

“As you can see?”

“Earlier, you seemed to be in terrible pain.”

“My throat was just clogged for a moment.”

“Your throat… you mean?”

“Yes.”

Raciel responded casually to alleviate any anxiety.

“I drank the decoction too hastily. The herbs got stuck.”

“The herbs got stuck?”

“Yes. Didn’t it look that way?”

“No. It didn’t look that way.”

“Well, then it can’t be helped.”

“But, Your Highness.”

“Why do you keep asking?”

“You definitely looked like you were in a very critical situation.”

“I’m fine. Can’t you see? I’m perfectly alright now.”

“But…”

Eventually, Gardin’s voice trailed off, and he shifted his focus to the vacant cup. It was the cup that once held the Mahuang Fuzi Xixin Decoction.

Was he reproaching himself? It appeared as though he believed that he should have drunk it before Raciel.

‘Sigh, it’s making him worry again.’

Raciel let out a faint laugh.

“Anyway, I drank it first because it’s a good thing. Even if it was a little strange, would I have drunk it right away? So don’t worry. If it’s really dangerous, even if you refuse, I’ll force it down your throat.”

“…Yes?”

“There’s no use in refusing. I’ll forcibly open your mouth, put a funnel in, and pour it in.”

“…Y-yes?”

“I hope you’ll be as loyal as you are now.”

“…”

“If you understand, clean up here. I’ll go to the bedroom and rest first. Oh, and…”

“Yes?”

“Thank you.”

“Y-yes?”

“If you didn’t understand, never mind.”

Wondering he shouldn’t have said it, Raciel hastily left the kitchen and retreated to his bedroom. 

There, he became lost in thought about the Mana Circle Slot he had acquired earlier, deeply concerned about how to best utilize its potential.

‘It said the storage capacity was 10 liters. Within that capacity, I can store matter mixed with mana.’

Of course, the way to fill it…

‘Consumption. In other words, I can fill it by eating.’

The message that had come to mind earlier had clearly informed him of that.

‘So… let’s start by experimenting if it really works.’

Raciel’s method of experimentation was straightforward – he would determine something by eating it. 

As he pondered this approach, a sudden thought crossed his mind, prompting him to scan his bedroom for something suitable to consume for the test. Eventually, he settled on a large crystal bottle filled with water.

‘Water would be perfect for this experiment.’

It was easily obtainable, not disgusting or burdensome to consume, and had a high LD50, making it safe to drink in large quantities.

‘LD50, that’s important. Especially now, when I have to try consuming a large amount.’

LD50 stands for “Lethal Dose 50%” and is a measure of toxicity used to determine the dose of a substance (such as a chemical, drug, or poison) that is lethal to 50% of the population or test subjects within a certain time frame.

‘There’s also the concept of LD100, but that’s rather imprecise. For example, the amount of poison that leads to death may vary among individuals because their constitutions are slightly different.’

In cases where a substance is only evaluated based on LD100, a tragedy could occur if someone drinks 800 milliliters, assuming it is safe because the lethal dose is 1 liter, only to succumb due to their body’s constitution. 

This is precisely why LD50 is utilized instead – to provide a more accurate measure of a substance’s toxicity and avoid such tragedies.

‘It’s like a value that says, roughly, at this point, the probability of death is 50%, and if you don’t die, you’ll at least suffer a lot, become a vegetable, or be semi-paralyzed, so be careful.’

Put simply, if you’re fortunate, consuming it may land you in the emergency room or intensive care unit. If you’re not, you’ll be sent straight to the morgue and high-five the King of Hell.

This holds true for all substances, including water, which has an LD50. For an average individual weighing 60 kilograms, the LD50 for water is roughly 5.4 liters, equivalent to 90 grams of water per kilogram of body weight.

‘So, with my current weight, the LD50 for water would be roughly… 3.9 liters.’

Raciel estimated the capacity of the crystal bottle by sight.

It seemed to be…

‘About the size of a 2-liter PET bottle. Perfect. That’ll do.’

Raciel felt relief wash over him as he considered the unlikelihood of any harm coming to him if he drank the entire contents of the bottle. As he picked it up, he noticed his arm trembling and brought the bottle to his lips, tilting it slowly.

‘Just holding this makes my arm tremble. Oh, this weak body.’

He grumbled, trying not to spill a single drop.

Gulp, gulp!

Cool water flowed down Raciel’s throat as he activated the Asrahan Core Technique. With the ease of giving an order, he commanded the Mana Circle.

‘I want to store the water I’m drinking now in the slot.’

Then, the Circle immediately responded.

Kiiiing-!

The Circle began to spin cheerfully. The rotation generated suction power, which sucked up all the water that was going down his esophagus into his stomach.

‘Oh? Ooh?’

Raciel found the experience fascinating. Despite clearly drinking a substantial amount of water from the bottle, he gulped it down without taking a breath, and his esophagus seemed to send the water down without a single drop reaching his stomach.

‘The water is being absorbed entirely into the Circle. The message was true.’

After draining the contents of the bottle, Raciel placed it down, now empty. Despite having consumed approximately 2 liters of water, he didn’t feel full in the slightest – it was an amazing sensation. Feeling like a hippo with a thirst for water, he desired more. With renewed determination, he left his bedroom and began to explore the other rooms connected by the hallway. Eventually, he discovered a living room, where he found four additional bottles of water.

‘Perfect. Let’s fill the remaining 8 liters.’

Determined to see the experiment through to the end, Raciel picked up another bottle and began emptying it without hesitation. After finishing the initial 2 liters, he added 2 more and continued to consume the water. Despite having consumed a significant amount already, he felt no abnormality in his body or sense of fullness. Encouraged, he continued to one-shot another 8 liters of water.

“…Ugh.”

To be honest, Raciel felt a bit proud of himself. When in his life had he ever consumed 10 liters of water in one go?

‘If I had, I would have died. LD50 or whatever, my stomach would have burst.’

A sudden recollection from his past flooded Raciel’s mind. He remembered a tradition where he was from, upon receiving a promotion, individuals were required to drink water. It was considered a bad habit to one-shot water from a pitcher containing at least 3 liters. However, nobody succeeded in completing the task, as after consuming roughly 1 liter, the overwhelming scent of water would cause them to run to the bathroom and release a torrential downpour akin to Niagara Falls. Raciel was no exception to this in the past.

‘But now it’s different. I drank 10 liters and there’s no burden at all. I don’t feel full, and there’s no water filling up my stomach.’

The 10 liters of water he had just drunk were stored directly in the Circle’s slot.

‘Let’s move on to the next stage of the experiment.’

He returned to his bedroom and went to sleep as if nothing had happened. The next day, he didn’t drink any water all day long. Instead, he slowly learned how to use the Circle’s slot.

‘When I feel thirsty… like this.’

Kiiiing…..

As Raciel slowly rotated the Circle, the response was immediate.

Ding dong!

[Releasing stored water from the Circle slot into your body.]

[Please set the release amount.]

‘0.1 liters.’

[Releasing 0.1 liters of water into your body.]

[Current storage capacity of slot 1: 9.9 liters]

Kiiiing-!

As the Circle rotated in the opposite direction, the water stored within was released into Raciel’s body with the aid of mana. The water flowed along with the mana, circulating through his blood vessels and being delivered directly to his body’s cells. Within moments, his thirst was quenched.

‘Wow. I’m like a camel. A human camel.’

Raciel mused over whether this was how camels felt, storing water and nutrients in their humps to survive wandering through the desert. 

He continued to use the Circle slot whenever he felt thirsty, which prevented him from experiencing thirst throughout the day, even if he didn’t drink a single drop of water. 

As time passed, he gradually learned more about the properties of the Circle slot, such as the fact that he couldn’t store a mixture of different foods or substances within it.

‘It can only store water if it’s water, or food if it’s food. Not even one menu per person, tsk. But… hmm, how do I empty the slot all at once?’

Midnight had once again arrived, enveloping Raciel’s quiet bedroom in darkness as he was lost in thought.

‘I have a rough idea of how to fill and use the slot, so now I want to try putting the elixir in it. But how do I empty it?’

He couldn’t release all the remaining water into his body at once. There was just too much water for that.

‘There’s still 8.5 liters left. If I released all of it into my body, I’d die instantly.’

So either he had to consume it slowly over time or replace a way to remove it all at once.

“….”

A possibility suddenly occurred to Raciel as he thought about the Asrahan Core Technique, which was frequently mentioned in the novel “Devil Sword Emperor” and its unique characteristics.

‘It’s a Core Technique specialized in mana absorption, amplification, and emission.’

That was the characteristic of the Asrahan Core Technique.

‘It might be possible with amplification and emission. Let’s try it.’

Raciel rose from his seat and stretched out his hand, focusing his concentration as he activated the Asrahan Core Technique.

Kiiiing…..

As Raciel reversed the rotation of the Circle, it responded immediately, as if it had been waiting for his command. He focused his concentration and determined to release all of the remaining water stored within the slot outside his body.

Kiiiing-!

Suddenly, the reverse rotation of the Circle intensified, causing the mana contained within to stir. The 8.5 liters of water resonated with the mana, resulting in an amplification of the water as it mixed with the mana.

[The stored substance in the Circle slot is amplified.]

[Releasing the stored 8.5 liters of water.]

As the water and mana amplified, it condensed into a potent form and followed the rush of the Circle, surging through Raciel’s heart and sprinting through his blood vessels.

Poooong-!

In a sudden burst, the 8.5 liters of condensed water were explosively launched in a sphere, shattering the crystal bottle his palm was pointing at instantly.