The Tutor's Day Off
Even on that day, I was tormented by Ye-eun’s sadistic, perverted whims, forced to endure multiple rounds of compulsory milking. By the time I returned home, I was completely drained, my voice weary as I muttered at the entrance.
"...I'm home..."
The front door slammed shut with a loud thud, but my younger sister didn't come out to greet me with her usual cheerful welcome. A bitter feeling settled in my chest as I thought to myself.
'...As expected, is it awkward because of what happened yesterday? Well, for someone as pure as Hyun-seo, it must have been quite a shock...'
Yesterday, while bathing with my sister, I had unintentionally thrust my fully erect, massive cock right in front of her face.
It wasn't my intention, but from the perspective of my sister, who didn't know the circumstances, it was certainly enough to be traumatizing.
I vaguely remembered her entering my room in the middle of the night, muttering things to herself, but I had been so groggy that I couldn't recall a single word.
I stood in front of her firmly closed bedroom door, hesitating for a long time as if it were a symbol of our drifting relationship. Finally, with my shoulders slumped, I turned and trudged toward my own room.
But just as I was about to enter, her door suddenly swung open. My sister, drenched in sweat, burst out and hurriedly greeted me.
"Oh, you're home, Oppa? Sorry, I was busy with something and didn't hear you!"
"Oh...? Uh, no, it's okay..."
Her face was flushed red, and she was breathing heavily, as if she had been doing some intense exercise alone in her room.
Contrary to my expectations, she wasn't acting awkward at all. In fact, her energy was higher than usual, and she was beaming at me. I blinked in confusion.
"...You must be tired, Oppa? You worked hard! Should I make you some tea?"
"...Oh... Th-that would be nice..."
"Yeah! Just a second, let me wash my hands..."
She wiped the sweat-drenched hair from her forehead, then dashed past me toward the bathroom sink.
After washing her hands, she brought tea to my room and immediately clung to my side, rubbing against me. My head was spinning; I had no idea what she was thinking. She just smiled brightly, pressed against me, and chirped.
"Oppa~ You know, tomorrow is a holiday, so you don't have work, right? Want to hang out with me tomorrow?"
"Ah, right. Now that you mention it, it is a holiday... Sure, why not?"
"...Yay! Let's have a cozy time at home, just the two of us... Sticking together all day long..."
"Uh... Th-that sounds good..."
She licked her lips, eyes narrowing into slits as she giggled. I broke into a cold sweat, desperately trying to avoid her intense, burdensome gaze.
Just then, my phone rang, and both my sister and I snapped our heads toward it.
Unsurprisingly, it was a call from Nayeon's Mother. My sister’s face instantly darkened, and she glared at the phone.
"...U-uh... Hello...?"
I cautiously answered the phone, wary of the murderous aura my sister was radiating. Nayeon's mother’s signature, honey-sweet voice began to flow from the receiver.
"Oh my, Teacher~ I'm so sorry to call while you're resting at night~ Did you get home safely yesterday?"
"Yes, yes... To what do I owe the pleasure..."
"Oh, it's nothing much~ I was just wondering if I could ask a huge favor of you~ If it’s a burden, you can refuse!"
"Wh-what kind of favor..."
"Well, you know, tomorrow is a holiday, so there's no school~? But I have to go on a business trip to the provinces~"
"So, I'll be away from home until tomorrow evening, and I'm just so worried about my daughter~"
"So, I was wondering, could you possibly stay with my daughter for just tomorrow~?"
"Excuse me...? With Nayeon...?"
My eyes widened in shock. Nayeon's mother continued nonchalantly.
"Yes! My daughter follows you well, and above all, I trust you, Teacher~ I really want to ask this of you, is that okay?"
Feeling the killing intent from my sister beside me growing more violent by the second, I stammered into the phone.
"B-but Nayeon is all grown up now, does she really need someone to watch her for just one day...?"
"Oh, about that, well... yes, it's not so much 'watching' her, but rather..."
"Oh my, Teacher, you know how it is~ If you leave kids alone for even one night, they turn the whole house into a total mess, ho ho."
...Well, as a shut-in loser like me, I couldn't exactly relate, but I got the gist.
In short, Nayeon's mother didn't want someone to 'care' for her daughter; she needed an adult to act as a monitor in her stead.
I glanced at my sister sitting next to me and mumbled with great difficulty.
"...Um, well... actually, I already have plans for tomorrow... I'm really sorry..."
"Oh my, is that so? What a shame, I really wanted you to take charge of my daughter....
Sigh, I guess it can't be helped. I'll have to cancel that bonus of OO million won I was going to give you...."
Hearing the amount she mentioned at the end, my eyes snapped wide open.
'...W-wait, OO million won...? I didn't hear that wrong, did I? With that money, I could easily buy my sister those expensive clothes she's always wanted...!'
Seeing me hesitate and unable to hang up, my sister glared at me, raising her eyebrows threateningly and thrusting her face right in front of mine.
After agonizing over it in my head, I finally shouted to Nayeon's mother in a panic.
"...Wait, just a moment...!"
...Of course, I had to pay the price for accepting Nayeon's mother's offer throughout that entire night.
My sister was deeply sulking, and no matter how much I tried to persuade her, she showed no signs of letting it go.
She understood that we were in a difficult financial situation and that I had no choice but to earn money, but it was still hard for her to accept feeling like she had been pushed to the background.
Finally, when I brought up the 'praise ritual' from last time as a last resort, she glanced at me, crossed her arms, and muttered primly.
"...Hmph, I'm tired of those childish things you do with those other girls. I'm all grown up now, you know."
"Oh...? I-is that so...?"
I was so surprised to hear words I thought would never come out of her mouth that I shouted in a loud voice.
She puffed out her cheeks, glared at me, then flipped her hair back and said haughtily.
"...I want to do something more adult-like now."
"A-adult-like...? What do you mean?"
She scanned me up and down, then suddenly pounced on me while I was off guard, pinning me down and straddling me in a cowgirl position.
She leaned down, expressionless, looking down at me while pressing her warm crotch firmly against my body, and whispered.
"...Praise me while patting my butt in this position. Then I'll forgive you."
"Hy-Hyun-seo...?"
And so, for the next few hours, I found myself repeatedly praising her while patting her panties as she sat on top of me.
In the process, my cock, pressed against her vulva, was pushed hard into her soft flesh, and inevitably, it became as hard as it had been last time.
I felt guilty, as if I were doing something terrible to my precious sister, so I blushed deeply and averted my gaze.
However, she shivered on top of me, her eyes filled with lust, swallowing her saliva repeatedly.
"....Haa, haa.... Keep going, keep going.... It feels good.... Oh, god...."
After what happened last night, I even felt a sense of dread, as if my kind and pure sister had been twisted into something else.
Eventually, she shivered violently on top of me, wearing an expression as if she had climaxed multiple times, before collapsing onto my chest and falling fast asleep until morning.
I could feel that the crotch of her underwear, pressed against my own, was damp.
I tried to rationalize it by telling myself she was just sulking and playing a more mischievous prank than usual, and eventually, exhausted, I drifted off to sleep as well.
The next day.
"...Must be nice, getting to spend the whole day with another girl. Have a good trip."
From early in the morning, I received a venomous farewell from my sister and headed to Nayeon's house.
Finally, standing in front of Nayeon's door, I let out a deep, heavy sigh.
'Sigh... It’s going to be a tough day today, too. Having to stick with Nayeon all day...'
Recently, I could feel that the students were treating me more and more like a convenient toy or a well-behaved pet to play with, and Nayeon was particularly extreme in that regard.
Moreover, Nayeon had the most violent tendencies of the three, which made being alone with her even more terrifying.
Fearing what kind of horrific things I might be subjected to today, I trembled and cautiously opened the door.
"....Ah, hello...."
Even though I muttered in a small, shrunken voice, no answer returned from the darkened house.
I pondered what to do, then decided to go to Nayeon's room to check if she was okay.
The house was unfamiliar, plunged in darkness unlike usual, so I walked toward her room, carefully silencing my footsteps as if I were a trespasser.
But just before I could open her door, a small voice came from behind me.
"....Is that Dad...?"
I turned my head in a panic, and there was Nayeon, her hair disheveled, her hand inside her pajamas, scratching her chest while letting out a huge yawn.
Seeing her walking like a zombie with both arms stretched out, stumbling like a newborn baby, it seemed she hadn't fully woken up yet.
Unlike her usual look with her bangs neatly combed, her hair was a mess, making her look quite different.
On top of that, she was wearing cute animal pajamas that didn't match her violent personality at all, making her look even less like the Nayeon I knew.
"...Ugh.... Why are you so small.... Hug me...."
Nayeon mumbled in a spoiled tone and walked right up to me.
Then, she wrapped her arms around me, closed her eyes, and stood there for a moment before slowly opening them, looking at me with bleary eyes.
Only then did she realize it was me. Her eyes widened, her face turned bright red in an instant, and she shoved me away violently, shouting sharply.
"Wh-wh-what the f*ck! Wh-why are you here!"
"Th-that, I was asked by your mother..."
As I explained, sweating profusely, Nayeon’s jaw dropped in disbelief, and she froze.
Then, she clutched her head, stomping her feet in frustration.
"....Ugh, f*cking hell, seriously....!"
I let out a deep sigh, feeling a strong premonition that it was going to be a rough day from the very start.
