Chapter 1

Prologue

For me, who has conquered numerous adult games from around the world, my favorite genre is undoubtedly magical girl games.

Also known as sentai or transformation heroine games.

These are games where a seemingly ordinary heroine transforms into a magical girl when demons appear, delivers justice, and then returns to her daily life.

Usually, in these kinds of games, the heroine gains power through sex.

And the medium for that power is sex with the protagonist… in other words, sexual arousal.

With that power, the heroine defeats the ferocious and powerful forces of evil one by one, eventually destroying the final boss and achieving a happy ending.

Of course, that’s not always the case.

Magical girl adult games often feature routes where the heroine falls into corruption or betrayal.

There are many stories where the heroine, unable to gain enough power through love, is mentally broken by multiple demons and ultimately betrays the protagonist, offering her body and soul to the final boss, leading to the destruction of Earth.

And I hated these corruption routes.

I tend to immerse myself in the protagonist.

No, not just immerse—I completely become the protagonist.

When I, as the protagonist, am barely able to flirt with the heroine, why should I be frustrated by having her taken away?

If it were just the villain stealing the heroine, that would be one thing, but when demons get involved, it always feels like a slap in the face.

From perverts who love anal sex to hypnosis, tentacles, egg-laying, beastmen, and electric shocks—how could anyone enjoy that?

Fortunately, all games allow you to choose your route.

That’s why, when I play magical girl games, I only go for the happy ending routes, avoiding these corruption routes except when I first started playing adult games.

Honestly, though, it does turn me on.

Anyway, the same goes for my favorite adult game, *Beast Slayer*.

From the first to the fifth installment, I’ve collected all the CGs except for the corruption routes.

And today, I’m playing the sixth installment.

The game company decided to bring together all the heroines from the first to the fifth installments and created this final sixth installment.

Of course, I bought the legitimate copy and inserted the CD into my computer.

With a pounding heart, I stared at the monitor.

According to the pre-release information, all five heroines appear in the sixth installment.

In the past, heroines from previous installments only made brief appearances in the next one, but now they’ve gone all out.

Well, I’ll find out the rest as I play.

Bam! Bam! Bam!

The upbeat background music of the magical girl genre always gets me excited.

The title screen showed the five heroines in their transformation suits, holding their weapons.

Living happily with the heroes who protect Earth…

From Monday to Friday, I’d have fun with one heroine, and on weekends, I’d have an orgy with all five.

The five most beautiful women in the world, all looking only at me…

As I thought this, a smile naturally formed on my face, and my hand moved to the mouse.

“Today, the heroines are all mine.”

Trying to calm my trembling heart, I was about to press the start button when…

Fizzle!

EP.1 The Returned (?) Me

“…Your Majesty!”

A rather elegant woman’s voice reached my ears.

“Ugh…!”

As I let out a low groan, my head feeling like it was about to split, the voice spoke again.

“Lord Demon King! Lord Tairat! Please wake up!”

She even tapped my body a few times.

By the way, Demon King… Lord Tairat?

I have my own name, so why Lord Tairat?

As I thought this, I suddenly remembered that the final boss of *Beast Slayer* was named Tairat.

‘…..’

For a moment, my mind went blank.

“Ahhh!”

I screamed and shot up.

Looking around in a panic, I saw a purple room.

Next to a bed that looked like it was made with over-the-top technology stood a demon in a scientist’s coat with long fangs.

And I knew exactly who this demon was.

“You… are you… Marcella?”

How could I not know?

That bitch who always modifies demons to attack the heroines.

Every time a tough demon appeared, it was a pain to play.

In the later stages, she gets torn to shreds by *Beast Slayer*’s finishing move, giving me a sense of satisfaction.

“Yes, it’s Marcella, Lord Demon King.”

“Lord Demon King…?”

I muttered with a dazed expression.

Marcella made a serious face.

“Hmm… Your vital signs are normal, but it seems there’s something wrong with your mind. Well… you did take a hit to the head from Celine, so it makes sense.”

‘Celine… you mean…’

*Beast Slayer* Celine, whose pre-transformation name was Adeline.

A slayer from another world, also the heroine of the fifth installment.

I decided to assess the situation.

Looking around quietly, I saw a familiar room layout.

Getting up from the bed to avoid Marcella, I thoroughly examined my surroundings.

A laboratory filled with all sorts of bizarre objects, a control room with five large monitors…

‘This is familiar… very familiar…’

After calming my chaotic mind, I realized.

This place is the base in Antarctica where Tairat, who came to conquer Earth, plotted his schemes… in other words, his base.

They say humans are creatures of adaptation? After some time, my head cooled down.

The feeling of being pulled into the monitor was real.

I was sure this wasn’t a dream.

For some reason, it seemed like I had entered the world of *Beast Slayer*.

‘So… I’ve become Tairat?’

Tairat is the ruler of the demon realm from another world called Erandel.

He covets Earth’s resources and leads his minions to invade, constantly tormenting *Beast Slayer*, only to be completely annihilated in the end, leaving not a single cell behind.

But through some method, he revives and appears consistently from the first to the fifth installment, a persistent boss.

He was naturally expected to appear in the sixth installment as well.

Also, compared to villains from other magical girl games, Tairat looks somewhat human.

A deliberate choice by the developers to increase player immersion in the corruption routes.

But I had killed this Tairat dozens, hundreds of times.

And now I’ve become Tairat…

The Tairat who must corrupt the heroines, gradually dragging them into the abyss of depravity.

This… this…

‘This is… freaking awesome?’

It was indeed freaking awesome.

And so, a week passed.

**

Honestly, damn it… I’ve often felt frustrated with the passive protagonist who just acts as a semen tank for the heroines.

I also didn’t like how, in the next installment, the protagonist would flirt with the previous heroine and then move on to another heroine.

Of course, the source of *Beast Slayer*’s power is sexual desire, so it’s an unavoidable choice to protect Earth.

But still, when I saw the ending where, after a long pure love, they confirmed their deep love for each other, my heart melted… but now I am Tairat.

The ruler of the demon realm who must use all his technological prowess to corrupt or kill the heroines.

In other words, I am the protagonist.

The protagonist I must empathize with.

Since I’ve become that protagonist, shouldn’t I act accordingly?

Anyway, right now, I’ve been defeated by Celine, the heroine of the fifth installment, and Marcella has used her transcendent technology to turn back time.

The point we’ve returned to is just before the start of the first installment.

The timing when I, having just arrived on Earth, must release demons to create chaos in the world.

Only Marcella and I know that we’ve returned to the past.

It seems this is the starting point of the sixth installment’s story.

“But isn’t this too overpowered?”

This was way too advantageous for Tairat.

In the first installment, Tairat was just a fantasy-like demon king without any over-the-top technology.

But now, having returned to the first installment with the experience of the first to fifth installments, the base is already dazzling.

Returning to the past with memories intact… did the developers think the corruption route was the standard and made it this way?

I’ll have to give them a piece of my mind when I get back.

‘Wait, why should I?’

Instead of complaining, I should be bowing in gratitude.

I know the entire story from the first to the fifth installments.

Although the branching paths will change based on my choices, having a guide is like having a significant cheat code.

“Huh? Lord Demon King… what do you mean?”

Beside me, Marcella, with her silver hair swaying, made a kitten-like expression.

She’s kind of cute… but her appearance is exactly like a clothed succubus, so she’s not my type.

I prefer humans, you see.

“It’s nothing… no, it’s nothing.”

I am now the ruler of Erandel.

I must show the dignity that comes with that.

Fortunately, Tairat’s way of speaking is something I’ve seen a lot in the game, so it’s easy to imitate.

Though it was hard to adapt.

I continued.

“Is Amducias ready?”

My demons gain power by capturing and violating humans.

The first boss of the first installment is a beastman with the upper body of a horse and a massive club.

A disposable boss used to awaken the heroine, only to die as a warm-up.

“Yes, but… I’m sorry to keep bringing this up, but wouldn’t it be better to send out Amon? Or kill Dr. Jennifer Cash…”

Amon is the mid-boss who appears near the end of the fifth installment, a large monster who uses hypnosis.

Marcella wants to send out a powerful boss to nip *Beast Slayer* in the bud.

Dr. Jennifer Cash is the genius scientist who appears as a key figure in the first to fifth installments, the creator of the transformation device.

It’s no exaggeration to say that the legend of *Beast Slayer* begins because of her.

If we wanted to take the easy way out, it would make sense to send out a strong boss like Marcella suggested or kill Dr. Cash.

But I had no intention of doing that.

If I couldn’t even have sex with the heroine who became a magical girl, why would I have enjoyed this adult game?

“No, we’ll go with Amducias. Don’t modify him, just have him on standby. And you stay here quietly.”

For now, I’ll follow the guide step by step.

But with a slight twist—I’ll insert myself among the heroines.

“Understood.”

I listened to Marcella’s answer with a satisfied expression.

“My fake identity?”

“It’s ready. Just enter the reactor and change your appearance, and everything will be perfect.”

“Good, I’ll disguise myself right away.”

The heroine of the first installment is Lee Sehwa, a Korean freshman at Korea University.

The childhood friend of the protagonist, Yoo Seunghyun, and still an ordinary college student.

Let’s get started.

“I have no idea what Lord Demon King’s intentions are…”

“I’ll tell you later.”

**

First day of the semester, Korea University.

“Excuse me.”

At my confident tone, a female student crossing the campus turned around.

Shoulder-length, wavy brown hair.

Bright brown eyes, a straight nose, and attractive lips.

A small face with perfectly balanced features.

With light makeup.

‘No joke…’

I inwardly marveled, disguised as a human.

Having only seen her in the game before, seeing her in person, right in front of me, made everything around me seem brighter.

The girl before me was Lee Sehwa.

Also known as *Beast Slayer Leona*.

Of course, not yet.

“Yes?”

Her voice was like a nightingale’s.

How could such a girl be Yoo Seunghyun’s girlfriend! Anger surged within me.

Stay calm, stay calm.

For now, I’ll stick to the plan, my disguised identity.

“Wow… no, sorry.”

I opened my mouth in surprise, and Sehwa burst out laughing.

Seems like she gets that reaction often.

Scratching my head, I said,

“I’m a freshman, and I need to take the ‘Understanding Science and Technology’ class. But I don’t know where the classroom is… do you know?”

“‘Understanding Science and Technology’? I’m heading there now, want to come with me?”

“Is that okay?”

“Why wouldn’t it be?”

With a clumsy smile, I thanked her and started walking beside her.

Ah… what a nice smell.

Sehwa uses fragrant shampoo… damn it, this makes me seem like a pervert.

Well, I am a pervert.

Let’s start with introductions.

“My name is Song Jihyuk. I’m a first-year in the Future Science department.”

At my words, Sehwa’s eyes widened.

Of course, she wouldn’t have seen me at the freshman orientation.

“I’m Lee Sehwa, also a first-year in Future Science… why does it feel like I haven’t seen you before?”

“I was sick and hospitalized at the time. I heard if you miss orientation, it’s hard to make friends with your peers… guess I’m destined to be a loner. I couldn’t even join the group chat…”

“I see… but what’s with the ‘loner’… you seem like you’d make friends easily.”

“Huh?”

“Your mask… um… it’s fine.”

Currently, I have a sickly body, but my face is incredibly handsome.

Like someone you’d want to protect?

Anyway, since Sehwa complimented me, Marcella’s arrangements seem to be working.

“Wow… to my face… but thanks.”

“Are you 20?”

“Yes.”

“Me too, so let’s drop the formalities. We’ll probably see each other often in required classes… shall I start?”

Sehwa is indeed very sociable.

That’s why she’s so popular at Korea University.

I nodded with a smile.

“Sure, you’re very friendly.”

“I talk a lot. But… you look a bit sick.”

“I’ve been in the hospital for months, so I haven’t gained much weight.”

“Months?”

“Yeah. I had an accident. A car hit me from behind.”

I subtly changed my expression.

A smiling face, but with a hint of sadness.

Sehwa looked flustered.

“Uh… sorry.”

“Nothing to be sorry about.”

“Where do you live?”

Look at her changing the subject.

So kind.

“I live alone in a studio near the school. You?”

“I also live alone. Not near the school, but two subway stops away. Oh, we’re here. This is it.”

Looking up, I saw a magnificent building.

As expected from the prestigious university in *Beast Slayer*, where money is no object.

Now it’s really starting.

With anticipation in my eyes, Sehwa said,

“Since this is fate, I’ll introduce you to my friends. I’ll add you to the group chat too. So don’t worry too much.”

“Thanks a lot. Really.”

“Thanks for what… shall we go in?”

“By the way, I don’t know the building layout. You’ll have to guide me.”

“Of course. Just trust me.”

I didn’t offer to buy her a meal or anything.

For now, becoming friends slowly is the priority.

Wait, Sehwa, I’ll save you from Yoo Seunghyun… that jerk who dares to mess with you.

Just until you transform.

To be continued―――――――――――――――――――――

---