I'm Going to Become a Cute and Pretty Female
Of course, it was difficult to see her as just Belial, the older sister I knew.
Sharp eyes, a completely different voice, and a strange, erotic sensation I had never felt before.
These traits were far too pronounced to ignore.
Above all, my sister had never worn such revealing clothes in her life.
She was always the sister who wore modest outfits, accompanied by a gentle smile and a soft, soothing voice.
Yet, for some reason, the moment I saw the summon standing before me, I found myself calling out for Belial.
In truth, there was something far more important than that.
The fact that the summon that appeared before me was a Demon.
Of course, there were cases where demons were summoned as familiars and contracted.
But demons were the only race capable of defying an absolute summoning contract.
Absolute loyalty to the contractor.
If it were a high-ranking demon, it would completely ignore that, craving all of the contractor's magical power until they lost their life.
Why on earth was a demon summoned?
And secondly.
Between that demon's legs, there was a truly grotesque object.
A bulging silhouette stood out through her clothes, and instinctively, I knew it was a male phallus.
She clearly had a female appearance, complete with very large breasts.
So why, then, was something like that between her legs?
“You have quite delicious magical power.”
That single sentence sent a chill down my spine.
It felt like a declaration of her intent to drain my magical power and end my life right then and there.
Regardless of the situation, I had to survive somehow, so I recited the contract incantation once more.
“I, Runisia Tiela. By the mark of the Soul Mark as my proof, I ask of you. Will you share your fate with me, become my strength, and—”
-*Whoosh!*
While I was reciting the contract, she closed the distance to me in an instant.
In any case, since she was summoned by my magical power, an inescapable binding would begin even if I didn't finish the full incantation.
But this demon had been acting as if nothing were wrong.
“Has our Runi always looked this delicious?”
While I was flustered by the demon's sudden actions, I heard a term of endearment that I couldn't possibly ignore.
That demon had clearly looked at me and called me ‘our Runi’.
It made no sense for a demon to suddenly use such a nickname—
“You *are* Belial, aren't you…!”
There was only one answer.
“Oh, no, I’m not.”
At that, she hurriedly covered her mouth with one hand and shook her head from side to side.
“You are.”
“I don’t know what you’re talking about.”
From that moment on, I focused more on proving that this demon was indeed Belial than on why she had been summoned before me.
“Then what is your name?”
“Beli… Astar.”
“Not Belial Astharot?”
“I don’t know who you’re talking about.”
“What is my name?”
“Runi. It’s only natural for a summoner to know—”
“That’s not my name, that’s my nickname.”
Silence began to flow.
Soon after, her gaze began to waver.
“How do you know my nickname?”
“Demons usually know more than other summons…”
“Sister.”
“Yes, Runi. Oh…”
It seemed she had no intention of hiding her identity anymore.
When she first appeared, she had been quite chilling, providing enough tension to make cold sweat run down my back.
But now, unlike her appearance, she showed many flaws and looked quite foolish at times.
“Sister, what are you doing here?”
“I’m sorry, but I’m not the person you know.”
“I first met Belial when I was 8 years old, and you look just like her.”
“8 years old? You met her when you were 7.”
“Oh my?”
“…Should I just give up?”
“Yeah, you’re so clumsy it’s making me laugh.”
I had intentionally provided the wrong information, and she had tried to correct it herself.
Now, I could be certain that this demon was indeed Belial.
“Sister, were you a demon all along?”
“If you think carefully about my name, wouldn’t you know?”
Belial Astharot.
Come to think of it—Belial was the name of a demon who incited greed, pleasure, and sexual corruption.
And Astharot was the name of a demon who was originally Astarte, the goddess of fertility and love, but became a demon associated with lust after her fall.
From the very beginning, my sister had been proudly revealing that she was a demon.
“Then… what about this?”
With trembling fingertips, I pointed at the object between her legs.
“Ah, this? It’s a dick.”
She revealed the identity of the object without a care and coolly pushed aside the fabric that had been covering it.
“Kyaa!”
I hurriedly covered my face with both hands.
Because it was an object I had never seen before in my life, my body moved naturally the moment that flesh-colored sight was revealed.
“Pfft, are you shy about seeing a dick?”
My sister slowly approached me. Then, she placed both hands on my lower abdomen.
Soon after, a crimson tattoo appeared on my lower belly, and that grotesque object surged upward.
“Can you see this?”
“…”
“The dick is twitching like crazy. Telling me to hurry up and ravish our Runi.”
My sister’s soft fingertips touched my collar. Soon after, the buttons of my shirt came undone naturally.
-*Slide!*
“Hkyaat!”
I hurriedly tried to put my shirt back on, but I couldn't pull it, as if it were being weighed down by an immense pressure.
“What cute breasts.”
-*Squeeze!*
“Hng-uh… W-what is… this suddenly… ah…”
At some point, my body had stopped moving as well.
I had to watch, unable to do anything, as my sister’s fingers touched me through my bra.
“We have to make a contract. A demon’s contract will be a little special.”
The tattoo on my sister’s lower abdomen glowed even brighter.
And then, my sister’s finger poked my nipple.
It was an incredibly precise touch through my underwear.
“Hng-yaaat…!”
“Your moan is cute. I can finally eat our Runi.”
At the touch of her hand gently stroking my chin, my body moved on its own.
Before I knew it, I was standing, facing her.
“Slurp…”
“Ugh?!”
Just then, her lips covered mine. At the same time, my hands moved without my permission to wrap around her waist.
“Slurp… slurp…”
While I was trying to process the shocking situation, the grotesque object that had surged high between her clothes revealed itself.
It entered my skirt and naturally began to lift it.
“Hng-ugh…”
As the tip of the object touched my panties, I couldn't help but let out a faint moan.
In the meantime, my sister’s tongue entered my mouth and stirred it to the fullest.
Very stickily, very erotically.
Her tongue, which felt exceptionally long, even wrapped around mine.
“Slurp… Runi, do you know how much I’ve waited for this day?”
“Waited…?”
“I’ve wanted to ravish you since the first time we met. I waited until you became an adult.”
Had my sister been a demon from the start, and had she stayed by my side all this time with the desire to do something to me since I was young?
The memories I had of my sister in my mind seemed to be turning black one by one.
-*Slide!*
Suddenly, my bra and shirt were completely stripped off.
Without even a moment to cover myself with my hands, my sister’s tongue touched my nipple.
No, it was swallowed into her mouth and disappeared from sight.
“Slurp…”
“Hng-euuuuuuuugh♥”
A stimulation I had never felt in my life bound my entire body.
My mind went blank, and both my legs began to tremble.
“Slurp… judging by your reaction, this is your first time.”
“Ugh-heuh-ugh…”
“Yeah, good. I hoped you’d be a virgin until I ravished you.”
She slowly stroked my nipple, which had become sticky with saliva, with her fingertips.
As my body shivered, my areola and nipple hardened and swelled up.
“S-sister…”
“Don’t worry. This is a contract.”
“How is this… a… contract…”
“I told you. A demon’s contract is special. Slurp!”
“Hya-ha-a-eung♥”
After saying that, she began to suck on my other breast.
-*Slide!*
“Hkyaat!”
Suddenly, my sister’s hand entered my skirt.
She began to slowly rub my vulva through my panties.
As my body grew hotter, I felt the sensation of my panties slowly becoming soaked.
It felt like she was spreading my vulva through the fabric, and she rubbed it strongly, putting force into her fingers.
“Hng-eu-geu-eu-ut♥”
“Slurp… Runi’s breasts are truly delicious. And your love juice is… slurp…”
“Haa… hng-ugh…”
“It’s tastier than I imagined. It was definitely worth the wait.”
I had to shake her off somehow.
I was thinking that I had to stop this act that was overwhelming me, even if I had to use magic, but my body wouldn't move at all.
“This… I hate it…”
“You hate it?”
-*Squish!*
“Heh-hu-gu-eu-ugh♥”
As I spat those words out, one of my sister’s fingers pushed aside my panties, went deep into my vulva, and came back out.
And she proudly showed me that finger.
“You’re leaking love juice like this, and you hate it? Really?”
My sister’s finger was covered in a very sticky liquid.
I knew, of course, that it had come from my own body, and a strange, erotic scent that I could never ignore pierced my nostrils strongly.
“You say you hate it with your mouth, but your body is being honest.”
My sister pushed me lightly, and I sat down on the floor as if being supported by something.
Naturally, my legs were spread wide.
-*Slide!*
At my sister’s light gesture, my panties began to come off.
I hurriedly tried to grab them, but they left my legs quickly, as if being pulled by a rough force.
“Your panties are so wet.”
“Ugh…”
“Sniff… haa… Runi’s scent… I think I’m going crazy…”
She brought her nose to the exact spot where my vulva had touched and took a deep breath, then stumbled once with an ecstatic expression on her face.
“This is the first time I’ve smelled such delicious love juice. Sniff… haa…”
Just as my sister was focused on smelling my panties, the clothes she was wearing slowly faded away.
Before I knew it, my sister was standing there completely naked.
And the object that had risen straight from her body was twitching, dripping sticky liquid from its tip.
“Hm? Do you want to see sister’s dick?”
“N-no…!”
My sister, who had approached closely, lightly stroked my cheek.
“Runi, I’ll make you into a very pretty female.”
“…What are you… saying…?”
“A very cute and pretty female who pants whenever sister shows her dick♡”
-*Chu!*
She lightly kissed my lips and revealed an erotic smile.
Then, she began to pinch and pull her own nipples with two fingers.
She opened her mouth wide, stuck her tongue out as far as she could—
-*Slide! Slide!*
She began to slowly stroke her object while holding it with one hand.
Whenever her hand moved forward, even thicker liquid flowed from the tip.
-*Throb!*
Instantly, a strong headache struck my brain.
Soon after, my mind became hazy. Along with this, a very deep, erotic scent wafted from somewhere.
The scent was coming from my sister’s grotesque object.
“Runi, let’s continue the contract. You’re going to suck sister’s dick.”
Without being able to think of anything else, I approached her and placed my hands on her pelvis.
At the same time, my tongue was stuck out long.