Terminally-Ill Genius Dark Knight

Side Story – [H-210 / Marin’s Diary].

Shortly after I opened my eyes and came into the world.

The air I first smelled was not pure.

Stale air mixed with the smell of the lab’s chemicals. The lab, with its countless glass tubes, was not the right environment for a child to grow up in.

I could see children like me curled up in fetal positions in glass tubes filled with vivid green liquid.

Chemicals and tools like countless test tubes were lined up to fill the lab, some of them new and some of them gone.

There were fewer and fewer glass tubes, too, but of course I didn’t know why.

I was naked, locked in a glass cage, watching spectacled nobles scribble in front of me day after day.

I was barely making it through the day, but my condition was not good to say the least.

I was bored, tormented by the knowledge I’d been force-fed since birth.

“H-210, can you hear me?”

After a few days of this.

When all the children in glass tubes were gone, except for me. I heard a man’s voice, inorganic and weary.

“…… Yes.”

I had no choice but to answer like that.

They called me H-210.

I don’t know why, but I was one of the subjects in an experiment to recreate the power of a race practiced in ancient times…….

I learned that many war orphans were used as test subjects.

I suddenly realized what had happened to one or two of the missing children.

They are all dead. Because they couldn’t prove their worth.

Sacrificed by those cold eyeglasses.

I was terrified, and my emotions were filled with anxiety.

Nevertheless, I always had to put on a bright smile and pretend to be the most useful person when the heads of the institute sought me out.

I must convince them that I can best handle the Mermaid blood that flows through me, for that is the only way I will survive.

“Hello, H-210. Starting today, you will live with me, not in a glass tube. I’m Jay, one of the Institute’s employees.”

Jay.

The good-looking woman who identified herself as such looked to be no older than twenty-five, at most. She had soft brown hair, shiny and bright.

I ended up living with her for a while.

Of course, I had no choice.

Like a cow being led to the slaughter, I could do nothing.

Just get used to being at the mercy of their choices.

But even in such a tragic situation, there was a glimmer of hope.

Jay, because she was my hope.

“What do you like to do?”

“You didn’t have fun when you were in the lab, did you? It was hard work.”

“I told them that such inhumane methods are not good… but the higher-ups didn’t listen to me…… I’m the last one standing, so I can’t help it. I apologize. I’m truly sorry.”

“Aww, isn’t H-210 a little too stiff to call you by your first name, since your hair is blue and resembles aquamarine… hmm. Yeah, how about Marin?”

Up until that point, I hadn’t been looking forward to it.

Everyone else had thought of me as a monkey in a zoo. A tool.

But not Jay.

She treated me like a person.

A person, not a tool.

I became curious and asked.

“Why is Jay so nice to me? They said I was a monster, forcibly infused with the blood of the Mermaids… I was a weapon to be used and killed on the battlefield…….”

Jay smiled warmly.

“I’ll confess one thing too. Since you told me your secret, I’m actually working here out of necessity because my family was taken hostage by those people.”

“Do you miss your family, Jay?”

“Of course.”

I shook my head, not understanding all she was saying because I didn’t have a family.

Jay stroked my hair and smiled lightly at me then, a transparent smile.

I can still remember her face, her body odor, the scent wafting through the room, all of it so vividly.

Jay said.

“Marin, if I were to leave you, wouldn’t you miss me?”

“……Jay, are you going to leave me…?”

I looked at her with anxious eyes, and she just gave me a hug, and how warm it was.

I don’t think many people realize how warm it was.

“That’s what family is.”

“So… is Jay family to me, too, and that’s why you’re so nice to me?”

“Yes! And there’s one more reason I protect you.”

“And what is that…?”

“That you’re still a kid.”

Jay smiled.

“Children need to be protected by adults, okay? You should always be able to protect those younger than you, too, because that’s what makes you a good adult.”

“Yeah… I’ll remember that. I think I understand now.”

I felt myself steadying myself as I joined her.

My handling of my powers as a mermaid became less risky, and I slowly began to open my eyes to my powers.

Jay and I slept in the same bed in the morning, woke up together, and trained again. Afterward, we would eat a delicious dinner that Jay would make for us…….

At night, we’d read fairy tales to the sound of grasshoppers and doze off.

When I look back on my childhood, I wonder if there was a happier time.

No, there won’t be. Definitely not.

But…….

As is often the case, those days were shattered by the smallest of triggers.

Ka-Boom!

(chaeng-geulang!)

One morning, out of the blue, dozens of men showed up at the house Jay and I were living in and started pushing her around and smashing furniture in the house.

“How long are we going to wait! I told you, we need the power of those mermaids to increase the power of the Imperial Family!”

“Mermaid, don’t call her Mermaid, this child has a name, Marin, she’s a person!”

“No, she is a weapon. And weapons are meant to be used in times of war.”

The men shook their heads emphatically.

They pushed her away, then walked over to me, who was still sleeping, threw back the covers, and shouted.

“Get up now. Weapon.”

“Stop it!”

“Shut up!”

Bang!

(kwang!)

The man swung his arm, and Jay was struck across the face and dropped to the ground, bleeding. She wasn’t dead, but she was so shocked she couldn’t think straight.

Jay. For the first time, I was gripped by the fear of losing someone.

“Dispose of Jay. You have violated the Imperial Household’s military code of honor, and this is a summary execution. Take her away!”

Terror.

A pressure that made my breath catch in my throat and sent my nerves into overdrive. What am I supposed to do here? Do I have to watch Jay die like this?

‘No.’

It was the first clear emotion I’d ever had besides anxiety, and it was an unfamiliar sensation for someone who endured day after day of boredom and pain.

“Stop…leave her.”

I pushed myself to my feet.

I grabbed the person who was dragging Jay and tried to rescue her, but they only scoffed at me and pulled out their weapons.

“You’re getting carried away with your own personal agendas… Ha, how about this?”

At that moment, the swords are raised, and the man’s sword is pointed straight down at Jay, drawing a sword path.

It happened in a split second.

And then.

Slash. Thud.

(tug. deguleuleu.)

Jay’s left arm drops, and with it, my pupils lose their light.

The man muttered with a satisfied expression.

“This way, you won’t get carried away anymore. Remember that. Next time, you’ll be my right-hand man.”

“How can you… you’re different, even if I’m not… you’re the same human being, so why are you tormenting each other……?”

“You have no right to question me. Just obey.”

“……No.”

I shook my head, clearly feeling the power coursing through my body at that moment.

As I feel tears well up in my eyes, obscuring my vision, I speak.

“You’re the weapon.”

“…Marin, no…….”

Jay’s voice as he reaches out to me with his missing arm.

But it’s too late.

At the same time, a wild tidal wave of magic erupted, completely breaking the limits of my control.

Ziiiiiing…!

An azure bow materialized, and the enemy’s urgent movements slowly came into focus.

Piing!

I immediately lost my cool. I fired a single arrow with all my might.

……That was the end of my memory.

When I woke up again, I was standing in front of the head of the criminal organization Lunatic.

Luna was at my side, and she spoke to me.

“What’s your name?”

“Ma…Rin.”

I barely spit out the name Jay had given me and looked around.

The woods around us were thick with darkness.

It was enough to make me realize that the place I’d been taken to was not a good place, at least not in the least.

“I am Luna, leader of the Lunatics.”

The woman called Luna said, and held out her hand to me.

“Enter the Lunatic. If you wish to take revenge on the Imperial Family for the pain they have caused you.”

“Jay… what happened to Jay, she’s the one with the brown hair… she’s the one who took care of me…….”

I snapped out of my trance.

Jay…….

Where the hell is Jay?

Luna listened to my rambling explanation, then spoke in a calm tone.

“If it’s Jay, she’s dead.”

“Dead… all of them?”

“Yes. And I need to make one thing clear.”

Luna paused for a moment, then pressed on.

“You’re the one who killed her.”

* * *

There was a long silence.

I couldn’t respond to Luna’s words as they dripped from her mouth.

When I finally opened my mouth, all I could say was…….

“It can’t be… it can’t be.”

“No, it didn’t. Don’t try to deny it. You already have your memories back, right? The [Watershot] you fired in your rampage. Amplified many times over by the power of the Mermaid, it was a killing weapon, and in the aftermath, Jay was caught in the blast, though she would have bled to death had you left her alone.”

The rest of her words fell on deaf ears.

“I, I saved her…….”

In that moment, a blur of memories accompanied by an excruciating headache. It was pulling me deeper into the mire of denying Luna’s words.

I killed her. I, Jay.

In that moment, I fell into a deep state of self-loathing as I remembered the monsters who had been experimenting on the human bodies for the Imperial Family. What they had demanded of me.

To strike with great force, to stamp on the enemy.

To kill people.

In the end, I realized, I had become what they wanted me to be.

Abandoning reason, killing the people in front of me. What was left of me after that?

Even in retrospect, I can’t figure it out. I was a coward.

I relied on my strength. No, it wasn’t really my strength.

Something forcefully planted in me by those I hated the most.

Relying on it, I attacked them in my eagerness to save Jay… and I didn’t produce the results I wanted.

“Come into the Lunatic.”

Luna said. Her golden hair and golden eyes were persuading me; they were both overwhelmingly awe-inspiring and dazzling at the same time.

“If you don’t come in, you’ll die here, but…….”

She rambled on, and at one point looked at me and said exactly that.

“Don’t you want revenge?”

The devil.

Jay had told me once, reading me a fairy tale. The devil preys on the weak minds of humans and makes them sweet offers.

Revenge, riches, power…….

They offer them what they desire and make it impossible to refuse.

Are humans any different?

I thought to myself as I watched Luna, but I finally had to make a decision.

The anger I felt was more than I could have imagined, and the guilt and pain I felt for Jay kept my feet moving forward.

And, sadly, Luna’s words were my salvation.

I wanted to give it back, even if it meant selling my soul to the devil.

Even though I knew how much the emotion of revenge would lead me down a rabbit hole. I was willing to drag my life through the mire to make a point.

I was willing to drag my life through the muck to let them know that they, the scum that made me this way and took Jay’s life, were more monstrous than I was.

So I said.

“I’ll… go with you. Let me join Lunatic.”

I decided to join her.

“You shall call me Master. You’ll start at the bottom of the ranks, but as soon as you’re able to wield that power, even a little, I’ll move you up the ranks. Merit is the only rule in Lunatic. You have talent.”

“Thank you… for that.”

Even if that talent isn’t really mine, an illusion created by someone else, and even if Luna knows it.

I needed to chase it like a moth, to use it. {1}

Just as the scum at the Institute had used me, I would take everything I had and push it to the limits of what I could do.

For Luna, who had saved me, and for Jay, whom I had killed.

Paradoxically, it was in killing her that I gained my greatest strength.

Three years passed.

I’m seventeen years old, and I still don’t control my power like I used to.

{TN Corner}

{1} : “Boon moth” could be firefly for a similar colloquialism

Jay’s pronouns are probably fem

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