I Became a Demon Lord

Let me ask you all something.

Have you ever looked at your own face reflected in the water? That face you glance at absentmindedly every morning. I've only just realized what an extravagant luxury that was.

Because for me, right now, it's impossible. What's reflected on the water's surface is a shapeless black blob. And that blob, as it happens, is me.

No eyes, no nose, no mouth. Just sticky ooze spreading out and clumping together, over and over. I'm a slime — the lowest-ranked monster you can find in a dungeon.

What a shame, truly. If I could evolve enough times, I might become something genuinely threatening, but that's a hopelessly distant dream. There isn't even another monster for me to eat, so I have no way to grow. It brings tears to my eyes.

Worse, I didn't even know where the exit was.

Once upon a time, I was a respectable adventurer myself. My name was... well, what's the point of digging that up now? There's no one left to call it anyway.

The root of it all was that I fell for a strange rumor.

Dungeons are domains created by Demon Lords. Which means that wherever a dungeon exists, a Demon Lord must exist somewhere within it — that's practically the definition.

The world is full of countless such dungeons. Everyone knows that. It's common knowledge. But the dungeon I entered was a different matter entirely.

It was the legendary stage where the Primordial Demon Lord, forged by the Demon God, and the Sun Hero, blessed by the Goddess, fought through the night in a battle to the death. A historic site straight out of a textbook. I'd even visited it once before, you know.

At one point, it was even revered as holy ground.

Of course, entry is barred now because it's too dangerous. The Demon Lord is dead, but the traps remained untouched — more threatening than any monster, in fact.

Not to mention anything worth calling treasure had long since been swept away. But the heart of the dungeon remained unknown territory. No one had ever properly explored it.

Who's to say a hidden hoard of gold and jewels wasn't still sitting there? Naturally, my companions all tried to talk me out of it. If it were me, I'd have done the same.

"Cowards can wait here."

Looking back, that was the last thing either of us said. My own foolhardy confidence dragged me straight into a trap. At the time, I genuinely believed I had died.

And then I opened my eyes, and this is what I'd become.

I wanted to bury my head in despair and refuse reality, but that resolve didn't last long either. Since this was my lot in life, I decided to push deeper inside. It wasn't as if I had ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠anything else to do.

And the dungeon, as expected, was completely empty.

Maybe even the rumors had been exaggerated.

Treasure hidden in a place like this?

A bold-faced lie, obviously.

It was a ruin where not a single monster dared show itself anymore. The Primordial Demon Lord and the hero who slew him had both vanished long ago, leaving nothing but their remains. How boring. A yawn rises all on its own.

A dungeon whose master is dead is nothing but an empty husk, not worth the effort of clearing. Adventurers had long since stopped coming. Well, who in their right mind would set foot in a useless grave like this?

Still, I resolved to make it at least as far as that unknown depths. Monster or not, I couldn't quite smother my curiosity. If I died again along the way, I'd simply have to call it fate.

So I crawled along the floor. For days — no, months, for all I know. To a slime, time means nothing. When I was hungry, I licked moss off the walls, and when a bug wandered by, I swallowed it.

Sometimes I wondered. Was there truly no way to return to a human body? And for some reason, today of all days, I found myself longing for the warmth of another person.

The balance of standing on two legs, the act of calling someone's name with your own voice. Everything I'd once dismissed as trivial now felt precious. It's a real riot, isn't it?

Only after losing something do you learn what it meant to you.

Anyone at all — I just wanted someone to talk to me.

But wishing changed nothing.

Even by my own estimation, my situation was pitiful.

No use cursing the gods over it, I suppose.

Then one day, while I was wandering in search of a way out, it happened.

Would you call it the ground beneath me? Suddenly, the floor gave way. Tumble, tumble. My gelatinous body tore apart and re-formed again and again as I fell.

At the bottom of that long tumble lay a chamber of unknown purpose. The ceiling was so high I couldn't see it, and facing me stood an enormous throne, silent and alone.

And draped across it, neck hanging limp, was the skeleton of a dragon. In life, it must have been a creature of such staggering majesty that it could burn a mountain to ash. It was so magnificent I couldn't help but marvel.

Beside it, a human skeleton sat frozen mid-grip, clutching a sword. The hand that had refused to release that broken hilt even in death left a deep impression on me.

And then — ah — it finally dawned on me.

Who these two were. The Primordial Demon Lord, and the hero who slew him — the ones who had existed only in the records. Never did I imagine I'd lay eyes on them here with my own... well, whatever I had in place of eyes.

A moving story, isn't it? That's what I thought, too. For about a moment. The problem was that my stomach kept growling. A real dilemma.

You see, I have an ability called Predation. The power to dissolve anything at all and turn it into nutrition. I spent a long while gazing up at that throne, deep in thought.

Should I eat them? No, this crosses a line, doesn't it? That's a hero, and the strongest Demon Lord in history, for goodness' sake. But passing them by felt like a terrible ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠waste.

...And yet, I could sense overwhelming demonic power.

What if there was a clue here to returning me to human form? Just imagining it set my heart racing. That's a perfectly natural reaction, I'll have you know. You all understand, right?

My conscience and my hunger went to war, and as always, the winner was decided from the start. I'm ashamed of myself — truly. But I had to survive.

Swallowing an excuse that didn't even deserve the name, I boldly climbed up onto the throne and devoured the bones of both the dragon and the hero without a moment's hesitation. Chew, chew. Honestly, they didn't taste great.

And at that exact moment, everything went black.

My consciousness flickered like a candle flame, then guttered out.

I'm not about to die all over again, am I?

Ohh, it's getting so dark. Not this...

In my next life, please let me be born lucky.

How much time passed after that? Drip. Drip. The sound of water falling from the ceiling barely coaxed my mind back to consciousness. I couldn't count the hours.

All I knew was that it had been a long time. Becoming a monster had apparently sharpened my senses. All five of them were keener than they'd ever been in my human days. First things first — figure out the situation, right?

Hm? Wait. Something was wrong.

This wasn't my formless, puddling body. There was something here with shape and center — a core to it. I reached down for the floor, and a hand touched the ground.

Is this real?! A hand. A hand, I say!

Though the two hands were different. The one braced against the floor was an ordinary human hand — but the other, resting against my chest, was covered in pure white scales. And its fingertips curved sharp as claws.

Like a dragon's. Could this... be me?

I jolted upright in shock.

My waist was unnaturally, almost unfamiliar-slim.

Every step landed with a center of gravity that felt nothing like before. My chest felt strangely heavy. Each time I moved my arms, something soft swayed back and forth.

And on top of that, the sensation of long hair brushing against my shoulders. Everything felt wrong, everything felt foreign. I looked around in a daze, and found myself drifting toward a pool of water.

This is strange. This is not a slime.

What on earth have I become this time?

Please, just let this one be normal.

The face reflected in the water was...

Hair of pure white, fading into pink at the tips. Rising above it, a pair of enormous white dragon horns. And crimson eyes, staring back at me from across the pool.

"...Who are you? Another adventurer, by any chance?"

I asked the woman in the water. Then I flinched. Because I couldn't quite believe that voice had actually come out of my own mouth. A lovely, low alto had rippled through the air — a woman's voice, the kind that could steal a heart.

Of course, there was no answer.

Well — that woman was me, after all.

Ba-dump. Ba-dump. My heart was pounding.

I became a woman?!

I laughed. What else could I do? I had prayed so desperately for a human body back. I hadn't expected it to turn out like this, but honestly? It wasn't half bad.

"Still, beats being a slime by a country mile."

It felt as though every nerve in my body was waking up, one by one. As if this body was whispering to me that it belonged to me now. What a marvel. Anyway — what was I supposed to do next?

Just as I stood there pondering blankly...

A voice sounded inside my head.

Neither man nor woman — ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠something other entirely.

It reverberated as if driven straight into my skull.

Artesia.

The name carved itself clearly into my mind. Strangely enough, I felt no resistance to it at all. As if it had been mine from the very beginning.

"What is that supposed to mean? Hey! You can't just drop all that and leave! Ugh, this is an absolute mess. The least you could've done was explain the basics."

All that came back was silence.

Some congratulations that was. Irresponsible to the very end.

I turned my gaze back to the woman in the water.

No help for it, then. Time to accept things.

I lived as an ordinary man, passed through an insignificant slime, and now — a Demon Lord, apparently. My name is Artesia. And as for my body... well, you can see it for yourself.

The thing I'd wished for never came true. Instead, I ended up with something else entirely — power I never asked for, and a body I never chose.

I'd given up on ever returning to being fully human. But if I couldn't go back ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠to how I was, then I'd simply have to find another way.

For now, let's just live enjoyably in this body.

After all, I'm a Demon Lord now.