The Man Whose Beloved Girlfriend Was Stolen Destroys Everything ~After Being Forced to Witness the NTR Scene, What Awaited Him Was a Dungeon. - Episode 1: The Worst Possible Beginning.

Episode 1: The Worst Possible Beginning.

Sweet, melting moans filled the humid air of the room.

There, straddling the hips of a man I had never seen before—her long hair swaying down to her waist—was the girl I loved more than anything in the world.

“…Eh…? Ha…?”

“Ohhh, it’s the boyfriend-kun! Hiii~!”

The man greeted me with an easy, carefree grin. I couldn’t find a single word to throw back at him. I simply stood rooted to the spot, paralyzed by the impossible scene unfolding right in front of me.

“Ri…o…?”

My mind refused to process it. Stammering, I called the name of my girlfriend—Niayama Rio—as though the syllables themselves might shatter the illusion.

I’d received a sudden LINE from her with nothing but an unfamiliar address. At first I had no idea what it meant, but a cold dread crept in—maybe she’d gotten caught up in something dangerous. So I came running.

And this is what I found.

What the hell is this?

“Aww, boyfriend-kun just collapsed~”

Still holding her close as though nothing was wrong, the man laughed. Then he finally turned her face toward me—the face of my most beloved girl, now wearing the expression of a bitch in heat.

“Aaah…♡ Haru-kun…♡”

With that utterly melted, dreamy look, she called my name—Shinomiya Haruto—in the sweetest, most intimate tone.

“…Rio! What the hell is going on?! Why are you with that guy…!”

The sight of her face, that syrupy voice—it broke something inside me. The dam burst. My words slammed into her, and after a brief moment of apparent thought, she answered.

“Sorry, Haru-kun…♡ But I already belong to this person now…♡”

She wrapped her arms around the man’s neck and resumed moving her hips without hesitation. All the while, he simply watched our exchange with open amusement.

“You—! What the fuck do you think you’re doing?! Give Rio back! Give me my girlfriend back!!”

Rage boiled over toward him too. I demanded answers. He just snorted derisively, completely unfazed.

“Hah. A guy who can’t even satisfy his own girl has the nerve to yap like that?”

“S-satisfy…? I’ve always done everything I could for Rio…!!”

“Kukuku. Isn’t that right, Rio?”

Still chuckling at how hilarious the whole thing was, the man called out to her as she kept grinding against him.

It’s fine. She’s just being forced. Threatened. That has to be it…! I trust Rio—I believe in her—

“I was never satisfied at all~♡”

“…Huh?”

I doubted my own ears.

Something inside me cracked—audibly, like glass.

She didn’t even pause.

“We only dated because we were childhood friends… but you’re shorter than me even though you’re in high school, your voice is tiny, you’re a gloomy shut-in with zero presence. Sure, you always gave me presents, so maybe you had money, but we never even had sex once…”

“But this person satisfies every single part of me♡ Not some ‘weak’ guy like you, Haru-kun—this strong man right here♡”

“…Ah… ah…”

She declared it with an expression of pure ecstasy.

My voice caught in my throat. I couldn’t speak, couldn’t force the words out. Tears spilled from my eyes whether I wanted them to or not.

“Aww~! Boyfriend-kun’s crying~! But come on, it’s your fault for being too weak to satisfy her, right~!”

“Ugh…!”

He tossed Rio onto the bed, strode over to me completely naked, and shoved hard against my shoulder where I had crumpled near the entrance.

“Well then, we’re gonna get back to it! Byeee!!”

He shoved me out and slammed the door shut with brutal force.

From inside came the renewed sound of her sweet, lewd cries.

The entire ordeal—from the moment I forced my way in until I was thrown out—lasted barely five minutes.

In a span of time that didn’t even amount to one-hundredth of all the moments I’d spent loving her more than anything—

“Aaaaaaaaaaaaaaaaaahhh…!!”

—I lost everything. My already pitiful pride. The girl who had been my entire world. Everything.

***

Staggering home on unsteady legs, I drew curious stares from passersby.

My vision blurred with tears. Worst of all was the nausea clawing at my stomach.

Everything Rio said was true. I’m only 163 cm tall despite being in high school. My voice is soft and timid. At school I’m the ultimate loner who can barely talk to anyone except her. I forced myself into a part-time job I hated—customer service—just so I could save up and buy her presents to look good…

…God, I really… really hate how weak I am.

Wave after wave of self-loathing crushed me. Ignoring the eyes on me, I sank into a crouch right there on the street. The nausea was unbearable; I couldn’t even stand properly. The clamor of the crowd faded away, replaced by a piercing ringing in my ears.

“…?”

Then I noticed something strange.

The asphalt beneath my palms, which had been faintly warm from the sun, had suddenly turned icy cold.

I lifted my tear-streaked face.

“…Where… am I?”

Endless corridors of smooth, inorganic stone stretched out in every direction—cold, sterile, utterly alien. The people who had surrounded me moments ago were gone. Only I remained, alone in this place.

The darkness ahead tugged at something primal inside me—fear.

“…‘D Disaster’.”

I understood instantly.

The extremely rare phenomenon in which ordinary people are abruptly pulled into the alternate space known as a “dungeon.” Commonly called D Disaster.

In Japan, there are roughly three reported victims per year.

And of those victims who were later “rescued” from the dungeon… zero.

Every single one discovered years later had been torn apart and devoured by monsters.

“…I really am the unluckiest bastard alive.”

The words slipped out—pure, unfiltered truth.

Nothing left. You’re better off rotting in a dungeon anyway. It felt almost as if the world itself had whispered the insult directly into my ear.

Yeah… this world really, truly hates me. After having the girl I loved stolen away, it still decides to kick me while I’m down. At this rate, I’m going to start hating it right back.

“…!!”

I clenched my fist so hard it felt like I might gouge the rough stone floor. Of course a powerless weakling like me couldn’t do any real damage. All I managed was to tear the skin from my knuckles; fresh blood seeped out and stained the ground.

But right now, that pain was the only thing keeping me grounded. Even if the world despised me, at least it hadn’t erased my existence yet.

Still… that was only a matter of time. If I just sat here, starvation and dehydration would finish me off slowly and painfully. I no longer had the strength—or the will—to resist.

“…Fine. Bring it on.”

If I let myself die of hunger without even trying, I’d go down in history as the coward who didn’t move an inch. To die with nothing to be proud of, nothing at all—that was unacceptable.

So I—

“I’m not ending like this…! I’m definitely getting out of here alive…!”

—I would escape this dungeon. Become the one and only survivor of a D Disaster. And in doing so, I would change who I was.

From a shadow no one noticed… to a glorious existence everyone would have to acknowledge.