Deflowering the Cheeky Younger Sister

"D-Don't move! This isn't a joke—I'll really blow your head off... Hwaaaang?!"

A sensation like a boulder crushing my lower abdomen forced an involuntary, childlike scream from my lips. It felt as if a massive wooden pillar, the kind used for the mansion's main beams, had pierced straight through me. When that thick column began scraping against my inner walls, my hole let out wet, squelching cries that echoed through the room.

I had no experience with men, but I possessed basic sexual knowledge. I wasn't completely ignorant of what climax felt like. Yet Arwen's cock shattered every notion I held about pleasure. The tingling I'd felt while touching myself with my fingers was nothing more than childish play. Arwen drove into me with brutal force, as if determined to prove it.

Even if it was only half, lusting after his own blood-related younger sister... I wanted to curse and resent Arwen, that embodiment of beastly desire. But—

"Hnnngh♡ Haa, haa... Hic?!"

Contrary to my thoughts, my pathetic lips only produced vulgar moans in time with Arwen's movements. Arwen, mounted atop his sister, bounced his hips lightly and asked,

"Feels good, doesn't it, Sophia?"

"D-Don't be ridiculous, hieeeng♡"

Arwen wore a satisfied expression as he watched me fail to properly retort to his mockery.

"You can't come yet, Sophia. You have to win the match, drive out your pathetic older brother, and take the position of family head, right?"

With a sly smile, Arwen grabbed my shoulders as handles and accelerated his thrusts. The ferocity made me fear my womb might be destroyed and I'd die. His weapon-like cock, with that axe-like protrusion jutting sideways, stimulated places my fingers could never reach, sending hot, electrifying sensations coursing through my entire body.

At the same time, I felt the pulsing of his member in my ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠lower abdomen. Like the heart of a wild horse galloping across the plains, Arwen's cock throbbed, and my vaginal walls trembled in response. The spasming of my abdomen told me climax was approaching. That I was about to lose to Arwen.

"Haaang, no, nooo♡"

Whether I was denying the climax or the defeat, even I didn't know. The meaningless cry meant nothing as the final moment arrived.

"Haaang, no, nooo♡"

Sophia had only been able to scream in ecstasy since I started moving my hips, but this cry was different. The end of her voice cracked roughly, like the scream of a female reaching the peak of a woman's pleasure. With her vaginal walls being conquered everywhere by my thick cock, Sophia was discovering new erogenous zones she hadn't known existed, crying out in delight.

Her pussy was screaming too. As my veined, blood-engorged cock stirred her slick, clinging inner walls—squelch, squelch, squelch, squelch—the lewd cries of her stretched hole mingled with Sophia's moans. Even a virgin could tell Sophia was about to climax.

"I'll soon pour my seed into Sophia's womb. This is your first creampie, isn't it?"

Hearing the word "creampie," Sophia shook her head frantically with a dazed expression. The hot sweat on her forehead splashed onto my cheek.

"Aaaang♡ No, not inside! Defiling my womb is absolutely... Hnnngh♡?!"

Sorry, Sophia, but I wasn't asking for your opinion. From the moment I tasted her insides with my cock, I'd already decided the first insertion would end with a creampie. Even if the developer himself descended into this room right now, I had no intention of changing it.

"Unfortunately, I don't need Sophia's answer."

Sophia glared at me as if cursing, "You demonic bastard." I wasn't sure if she actually meant to say it, but the moment her lips moved, I sealed them with a kiss. At the same time, I grabbed both her wrists and roughly pinned them to the bed.

Pressing close against Sophia, I increased the speed of my hips. Her vigorously bouncing breasts brushed their hardened nipples against my chest. What had once been soft nipples now felt stiffly erect. Sophia's firm yet soft thighs slapped against mine, creating a beautiful drumbeat. Our hot sweat mixed on our skin. Our slick saliva mingled on our tongues. Two beings born with different bodies were merging into one. The burning sensation that made me feel as if my entire body would melt and be reconstructed reached its peak at my cock.

The urethral opening, pressed against Sophia's cervix just before ejaculation, twitched.

‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠

"Mmph♡ Mmm♡ Mmmph♡"

Though Sophia had insisted creampie was absolutely forbidden, her brother's semen soon poured into the womb she'd told him not to defile. A liquid far stickier than saliva or bodily fluids erupted from the widened urethra, painting Sophia's vaginal walls. Simultaneously, her lower abdomen began convulsing as if struck by an earthquake, and finally, the female's climax arrived.

Even the strong-willed Sophia, being a woman, couldn't overcome the faithful instinct of a female conquered by a male and bearing his offspring. The victory cry announcing my triumph burst from Sophia's lips.

"Hnnngh..."

With our mouths connected, Sophia's moan reverberated through my entire head. It felt as if I'd put earphones in my mouth and maxed out the volume. The semen filling Sophia's womb and vaginal walls leaked out around my embedded cock, soaking my balls and pubic hair.

Pulling my mouth away from Sophia, whose eyes had slightly rolled back to reveal the whites, I withdrew my spent cock. Transparent white threads connected Sophia's upper and lower lips to my tongue and cock respectively. Wiping the quickly cooling white threads from my thigh, I asked her,

"Haa, haa... How was your first creampie?"

"Haa, haa..."

Sophia couldn't answer, only breathing roughly. Her breasts, covered in some unknown salty liquid, rose and fell repeatedly.

"Don't want to answer?"

I grabbed Sophia's unresponsive breasts with both hands and kneaded them. My ten fingers sank into the elastic, soft mounds. When I rolled my tongue around the glistening nipples atop her breasts, Sophia's entire body twitched, perhaps from the lingering afterglow of climax. As expected, there was a slight salty taste.

At that moment, Sophia regained her senses and spoke in a pleading voice.

"Hic♡ D-Don't suck right now. Please, Arwen."

At Sophia's plea, I removed my tongue from her swollen nipples. Then I asked once more about her first experience. After a moment of hesitation, Sophia opened her mouth.

"It felt like flames starting from my lower abdomen and burning through my entire body... I've never felt anything like this in my life."

Her impression was surprisingly honest. I'd expected her to say something like "Your pathetic cock didn't feel good at all" or "It was dirtier and more blasphemous than an orc."

"Then the match is over."

"Yes... You're right."

Sophia spoke while wiping her brother's semen from her hole with her fingers. Having honestly admitted her climax, Sophia asked me a question—the punishment the winner would impose ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠on the loser.

"What are you going to do with me now? Exile me to the farthest edge of the North where no one goes? Or..."

Sophia trailed off and made a gesture of slicing her throat with her thumb.

"Completely remove the thorn in your side from this world?"

"Hmm, what do you think you would have done if you'd won, Sophia?"

Sophia took my hand and guided it to her own neck, answering without hesitation.

"I wouldn't have given you a peaceful end. So even if you rape and kill me right here, I can accept it. The loser has no value in living."

Then she closed her eyes with a calm face, as if prepared to accept any fate. I could feel the pulse of Sophia's slender neck in my hand. If I applied force, Sophia would accept her end just as she'd said. But I didn't apply force. I removed my hand from Sophia's neck.

"You want ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠me to kill the strongest Reinhardt? Unfortunately, Sophia will have to work for the Reinhardt family for the rest of her life."

"That means..."

"Yes, stay by my side, Sophia. Help me. Crush the jackals targeting the Reinhardt family."

Sophia spoke with an incredulous expression.

"Ha, aren't you worried? What if I betray you?"

I shook my head at Sophia. As a result, sweat droplets rolled down my neck and fell onto Sophia's face. But Sophia didn't even seem to notice.

"Even for the sake of your own pride, you won't betray me. After all, you tried to keep your promise with that idiot Leopold."

"..."

"I'll say it once more. Stay by my side."

Hearing my firm yet sticky answer, like freshly ejaculated semen, Sophia let out a small sigh and closed her eyes. With her face showing no movement of her lips, as if deeply contemplating something, only her hair swayed in my breath. After a moment, Sophia opened her eyes and spoke.

"I lost. Both in the match and in being worthy of the heir's position. It's your complete victory."

The younger sister declaring her older brother's victory wore a faint smile. And the moment the word "victory" left Sophia's lips, a notification window appeared between us.

"Somehow, my heart feels lighter. The way I hated and disliked you now feels foolish."

But it wasn't only Sophia who felt relieved. The cruel fate of possessing the adult-game version of Najakgem—not even a mischievous joke. Despite various twists and turns, I'd finally succeeded in defeating Sophia, the final boss of the Academy arc. Not with sword or magic, but with my cock.

Of course, I hadn't reached this point through my own strength alone. The faces of the many people who'd helped me, a man possessed into a world with no relatives, came to mind. Raibel, Masha, Emilia, and even Cordelia. Without their help, I would have become a emaciated corpse without a drop of blood. It would have been quite a pathetic sight.

While savoring the afterglow of victory, a notification window suddenly appeared, assigning a new quest. I wanted to tell the unnecessarily diligent system to show some tact. I was forced to read the text floating before my eyes. And as expected, the quest content was far from ordinary.

'...You're incredible, Developer-nim.'

The trait given as a penalty was [Short Life]. Just from the name, I immediately understood what kind of trait it was. I didn't know what the criteria for "short life" would be, but a wry laugh escaped me at the thought of game over if I failed to impregnate both sisters—an incest-obsessed developer. As expected, the game I'd possessed was indeed an adult game. A quest this insane was necessary for it to be an adult game.