After being officially appointed as a Hero, I carried out requests on the front lines of the War against Demons.

In my spare time, I would follow the Bamboo Hat Mister on ‘secret missions’ outside of regular requests, experiencing and learning various things.

…It was during that time that I first met that girl, Cheong-yi.

The Bamboo Hat Mister, who had received the ‘Rebuild the Demonic Cult’ mission, took me to the Shandong Peninsula, and the person central to that mission was none other than Cheong-yi.

It was the same then as it is now.

The only differences were that Blindman Shim had already passed away, and that Cheong-yi had already lost half her sight.

But just like I did now, the Bamboo Hat Mister told her the ‘truth of the Demonic Cult’.

That girl, Cheong-yi, chose the path of drawing the Demonic Sword and accepting her fate.

『Kuaaaargh-!』

The Divine Sickness inflicted a tearing pain throughout Cheong-yi’s body back then, too. And I was the only one fidgeting restlessly as I watched her writhe in agony.

『…Is it really okay to just leave her like that?』

『…….』

『She’s in so much pain, though?』

Of course, it wasn't as if the Bamboo Hat Mister had a comfortable expression on his face either.

『…This is something that child must endure. It is a path she chose herself.』

『…….』

『…There's nothing we can do anyway, so don't do anything foolish. Her entire body is filled with the energy of the Demonic Sword. If you touch her carelessly, she might fall into qi deviation instead.』

It was just that his greater experience allowed him to be a bit more desensitized and calm than I was.

It was clear he was feeling the same kind of discomfort as I was.

…In reality, there was nothing wrong with what the Bamboo Hat Mister had said.

There was no room for us to intervene in the succession process of the Demonic Sword, which had become fixed over generations.

We could only tell her the truth regarding the stories of the previous Heavenly Demons and the traditions of the Demonic Cult, which her father had hidden.

That was the extent of our role.

As the Bamboo Hat Mister said, we weren't the ones directly inflicting the pain, and it was a path she had chosen for herself.

But why?

『…You rascal.』

My naive younger self couldn't erase the guilt of having brought such pain upon that young, pitiful girl.

She would have completely lost her sight if left alone, yes, but if we hadn't told her the truth, she wouldn't have had to suffer like this.

…Right.

I wonder if the feelings of Cheong-yi’s father, Blindman Shim, were similar to this.

Knowing that neither choice would bring peace of mind and that I had no power to solve it, I found myself approaching her unconsciously.

It wasn't because I had thought of a special method. It was just an instinctive movement born from the feeling of wanting to do ‘something’.

Did he sense the weight of my footsteps? Or perhaps he had faith that I wouldn't do anything to harm Cheong-yi?

The Bamboo Hat Mister only called out my name to dissuade me, but he didn't come over and grab my shoulder.

『…It’s no use. U-jin, whatever you try to do will only stimulate her overflowing Mana Circuit and cause her more pain.』

And those words, spoken by the Bamboo Hat Mister to stop me, became a hint.

『…So, to put it simply, she’s in pain because her mana is full. Is that it?』

『……?』

Having reached Cheong-yi’s side, I sank my fangs into her neck.

『……!!!』

Along with that, through my fangs, which were a medium for ‘Vampire Black Magic’, I began to suck out the black energy that filled her body.

[ is activated.]

[…Warning! An unknown magic formula is reacting to your mana.]

[The activation conditions for 's hidden perk, ‘Subordination’, have been met.]

I couldn't read all the messages that popped up before my eyes, but they gave me the confidence that what I was doing wasn't wrong.

Filled with even more conviction, I absorbed that dense, black mana without delay.

As a result, I was able to suck out the energy that had not only filled her Mana Circuit but also lingered throughout her body, causing her pain.

[Do you want to subordinate ? Y/N]

That was the beginning of the ‘subordinate relationship’ between Cheong-yi and me.

* * *

Ughh-

My dulled five senses slowly began to function again, and along with my stiff muscles, I felt a stabbing pain in my left shoulder blade.

“…Are you awake?”

“……”

Soon after, I heard that girl Cheong-yi’s voice and realized that I had fainted.

At the same time, I felt an awkward softness behind my head.

The fact that there couldn't possibly be a pillow in a cave like this made me realize I was resting my head on Cheong-yi’s lap.

I immediately sat up.

Thud-

“Please lie down a little longer.”

…But her hand pressing down on my forehead made me lean my head back again.

“Your healing speed was unusual, so I left you be, but the wound on your shoulder is not shallow.”

“…How much time has passed?”

“Not long. If I regained consciousness right away, then not even a 15 minutes has passed.”

“How’s your body?”

“I am unharmed.”

“……”

“…Thanks to you.”

…It seemed to have been a success, for now.

I hadn't considered the possibility of fainting, though.

It seemed the unplanned damage to my shoulder was more severe than I thought.

Haaah-

Finally letting out a sigh of relief, I belatedly opened the system window to check the messages that had appeared while I was unconscious.

[Do you want to subordinate ? Y/N]

[Yes.]

[Warning! The data on the ‘Subordination Rite’ is incomplete.]

[Missing data is being supplemented by .]

[Forming a Subordination Contract with .]

[A strange, permanent change has occurred in your Mana Circuit.]

[The upgrade conditions for have been met.]

[Awakening .]

…It seems I somehow managed to finish the Subordination Contract while unconscious.

Cheong-yi’s comment about my unusual healing speed was also likely thanks to the upgraded Vampire Trait.

■Whole Vampire (★★☆)

[Vampires possess superior regenerative abilities compared to others. (This effect is drastically increased when absorbing the blood of a hunted target.)]

[Can form Subordination Contracts depending on conditions. (Current Subordinates: 1. Shim Cheong)]

Swoosh-

Turning my head to look up at Cheong-yi’s neck, I saw that the spot where I had sunk my fangs was now engraved with the unique red Magic Circle of the Vampire Clan, signifying a ‘Subordination Contract’.

“…What in the world did you do? When I regained consciousness, I found that you had bitten my neck, and the excruciating pain that pierced my entire body was gone.”

“……”

“From the circumstances, I could tell it was your doing, Orabeoni… but I cannot fathom the principle behind it at all.”

Pfft-

“Of course you can't.”

“……?”

“This is the ‘Blood Demon Art’ of the long-lost Vampire Clan.”

If I had shown this scene to Jerry, he probably would have lost his composure all over again.

Subordination.

Along with ‘Granting Racial Traits’, this was another Trait that formed a core part of the ‘Blood Demon Art’.

If the first characteristic of the ‘Blood Demon Art’ is to grant the Vampire racial trait to humans or other demi-humans through Black Magic, just as Jerry did on the Guardian Train...

...then this Subordination could be called the ‘second characteristic’.

It doesn't just stop at granting the Vampire racial trait; it forms a master-servant relationship with the target of the blood-sucking and allows for the absorption of the target's traits.

It was a Trait that truly suited the name ‘Vampire’.

It was thanks to this very Trait that the Vampire Clan, which maintained only small numbers, was once renowned within the Demon King's Army as the ‘Vampire Brigade’.

Due to their racial characteristics, even if the number of true vampires was small, each vampire who commanded numerous subordinates already formed a considerable force on their own.

As the owners of the Trait, the vampires knew their subordinates' abilities better than anyone and could command them in battle with optimal synergy.

As battle commanders, each and every one of those vampires was a force that could be called nothing short of a calamity.

Of course, it wasn't as if Cheong-yi would understand if I explained all that.

So I cut out the preamble and summarized only the important parts.

“To put it simply, the excruciating pain you experienced was because the Demonic Sword's energy overflowed even after filling your Mana Circuit. You can think of it as me having absorbed that excess.”

“…Absorbed.”

This was the third path I had told Cheong-yi about.

Because it was a defunct form of Black Magic, no detailed records or studies of it remained.

The Subordination trait of the ‘Blood Demon Art’ was capable of absorbing even the powerful energy emanating from the Demonic Sword.

By dividing the vast energy of the Demonic Sword, which one person had to bear, between two bodies, the pain of the Divine Sickness caused by the mana overflow would disappear.

Of course, that didn't mean I had taken exactly half of the Heavenly Demon's power that Cheong-yi possessed.

Energy has purity.

A phenomenon similar to osmosis occurs, so the purer energy had already been drawn into Cheong-yi's Mana Circuit.

What I absorbed were the impure dregs that had remained in her body causing her pain.

In terms of actual energy, I couldn't be sure, but the ratio was probably around 7:3.

…Of course, even that much was a power so great I wouldn't be able to utilize it properly for a while.

As if something had occurred to her, she couldn't smooth her furrowed brow even after my brief explanation and asked me in a rather serious voice.

“…My father once taught me that everything in the world comes with a price.”

“Well, yeah, usually.”

“…That Blood Demon Art seems to have had only positive effects on me. In that case… could it be that something is wrong with your body, Orabeoni?”

Pfft-

Is her intuition naturally sharp? She immediately pointed out the eternal truths of ‘give and take’ and ‘high risk, high return’.

To this girl, I revealed one of the hidden facts about this ‘Subordination Contract’.

That is.

“Well, there is a price. We did form a Subordination Contract, after all. For example…”

“……”

“Put both hands on your head.”

“…H-Huh?”

Swoosh-

“Wait… why are they moving on their own—.”

“Shake them like crazy.”

Flap, flap-

…The fact that the Subordination Contract involves a kind of compulsory force.