The Tutor's Burden and the Sister's Reward
Just then, the sound of the front door keypad being punched in echoed through the apartment. Moments later, the door swung open, and Nayeon’s mother, having finished her workday earlier than usual, bustled inside. "Oh my, it’s so hot out there! I wonder if our lovely girls are studying hard?"
As she stomped toward Nayeon’s room, Nayeon’s eyes widened in panic, and she shoved me away with a frantic force. She looked down at the sticky, white mess of semen staining her school skirt, scrambled to find some tissues, and then, realizing she wouldn't have enough time to clean it properly, simply threw a blanket from the chair over her lap. I, too, scrambled to pull up my pants and plopped down in front of my desk, pretending to be deep in the middle of a lesson.
The next moment, Nayeon’s mother burst through the door, scanning the room with a bright, cheerful smile. She paused for a split second, her gaze lingering on the blanket-covered skirt with a knowing, suggestive smirk, before she chirped in a welcoming tone.
"Unnie! Why are you so pretty today? You look like a total celebrity!" Seunghee chirped, waving her hands with a bright, innocent smile. Nayeon’s mother covered her mouth, giggling coyly.
"Oh, you! I told you to only call me that when it's just us! You're making me blush, ho ho."
"Aww, if we don't call you Unnie, what are we supposed to call you? Tee-hee." As Ye-eun chimed in with a sweet, sugary laugh, Nayeon’s mother beamed, clearly pleased, and bowed her head toward me.
"Hello, Teacher~ You must be having a hard time. I bet my daughter is the most troublesome one, right? Ho ho."
"Ah, no... I'm fine, really..."
"Oh, don't be so modest... Hey, fix your clothes properly. The teacher is right there, what kind of appearance is that..."
"Ugh, don't touch me..." As her mother reached out to straighten her disheveled shirt, Nayeon snapped, pushing her away aggressively, terrified that the semen on her skirt might be discovered. Undeterred, Nayeon’s mother crouched down right in front of her and began buttoning her daughter's shirt herself. As she did, the red lingerie peeking out from between her knees under her tight office skirt was clearly visible, forcing me to turn my head away, my face burning red.
Finally, Nayeon’s mother stood up, leaned toward me, and deliberately let her breasts sag forward while tucking her hair behind her ears. She spoke in a soft, honeyed voice.
"Oh my, you must be exhausted~ Please, have some fruit while you work, Teacher~"
"A-ah, th-thank you..."
A heady mix of a mature woman’s scent and expensive perfume wafted from her cleavage. Behind her, Nayeon stood with her arms crossed, glaring with a look of pure displeasure at the sight of her mother thrusting her chest at me.
Five minutes after she left the room, she returned with a plate piled high with sliced fruit. "Eat up and please, take good care of our girls, Teacher~"
"Y-yes, of course..."
Overcome with guilt—having spent the entire time masturbating in front of the students instead of teaching—I hung my head low and mumbled into my chest. Ye-eun, meanwhile, happily bit into a piece of fruit, cupping her cheek with her hand. "Oh yeah, this is the best~"
For a while, silence filled the room, save for the sound of them chewing. Eventually, Nayeon peeked under the blanket, saw the mess, and tossed a command at me. "....Hey, give me some tissues."
"O-okay..." I quickly pulled out a few sheets and handed them over. Nayeon wiped her skirt once or twice, then tossed the tissues and the blanket aside as if it were nothing.
After that, the students went back to their usual routine, lounging on the bed, scrolling through their phones, or checking their makeup in the mirror. Since I hadn't even managed to reach the promised ten masturbations, I had no leverage left to force them to study. Of course, it was doubtful they would have listened even if I had succeeded.
I sighed deeply, my head bowed. '...There's no help for it. I'll have to give up on tomorrow's test and just try to get them to listen to the lesson before the next one...'
"...What are you doing? Not gonna teach?"
Suddenly, Nayeon, who had been resting her chin on her hand while scrolling on her phone, spoke up in a blunt, indifferent tone. I was so shocked that those words had come from her that I whipped my head around to look at her. She didn't even glance my way, just muttered lazily.
"....You said you'd tell us the problems that would be on the test."
"O-oh... r-right, I did..." I stammered, glancing at the other two students. Gathering a bit of courage, I added in a firmer voice, "Th-then... shall we look at the textbook together, everyone...?"
For the rest of the time, I pointed out about twenty likely test questions to the disinterested girls and explained them with all my might, spitting out words until my throat was dry. Knowing full well that none of them were smart enough to understand the logic behind the problems, I desperately repeated the answers over and over, hoping they would at least memorize them. Of course, if the school teacher changed even a single number, they would get it wrong, but it was better than doing nothing at all.
By the time the lesson ended, I was completely drained, but I felt a strange sense of relief. Even then, the girls remained indifferent, lying around, checking their phones or mirrors, not paying a shred of attention to me. I offered a bitter smile, slowly stood up, and spoke to them.
"Th-then, good luck on the test tomorrow, everyone...!"
"Yup, thanks for your hard work, Oppa!" Seunghee, who had been busy touching up her makeup, waved back with a nonchalant smile. Just as I was about to force a smile and head for the door, I caught a glimpse of Nayeon staring intently at the textbook I had left open on the desk.
'Huh...? What is she planning...'
I left the house, trudging home with a head full of questions.
From the next day, Nayeon’s school went into exam week, so the tutoring was put on hold. The official reason was to allow them to focus on their other subjects. Of course, I knew that for these girls, exam week was nothing more than an excuse to get out of school early and play to their hearts' content.
During the break, I went out to the city center with my younger sister, who had just finished her own exams.
"....Your exams are over, shouldn't you be out with your friends...?"
"Nope, I'm hanging out with them tomorrow! Today is my date day with Oppa~" My sister replied in a bright voice, linking her arm affectionately with mine. Unlike me, a gloomy loner, she had a bright, outgoing personality, so I was sure her friends had invited her out, yet she always made sure to spend a day or two out with me like this.
I assumed my kind sister was just doing me a favor, trying to drag me out of my room to see the world, and I felt secretly grateful. Of course, aside from the gratitude, it was a bit embarrassing to be walking through the crowded city center with her clinging to me so tightly.
When she pulled my arm so close that her small breasts were pressed firmly against it, I finally couldn't take it anymore and whispered into her ear.
"H-Hyunseo, if you stick so close, won't people get the wrong idea...?"
"...So?"
When she immediately shot me a sharp, deadpan look, I felt cold sweat trickling down my back despite the sweltering heat.
"A-ah, never mind..."
"Oh, Oppa! Let's eat cake at that cafe over there! Hehe, it looks so good..." Her expression brightened instantly, and she beamed, shouting with joy. As we headed toward the cafe, my phone suddenly rang. I checked the caller ID—it was Nayeon’s mother.
'Huh...? What is this? Don't tell me the grades are already out...? I didn't think she'd bring up grades for a while after what happened last time, so why...'
Flustered, I swallowed hard and answered the phone with a trembling voice.
"H-hello...?"
"Hello, Teacher..! Oh my, oh my, you won't believe this! Nayeon, she actually..."
Nayeon’s mother launched into a rapid-fire, excited explanation the moment I picked up. As I listened, my eyes widened in sheer disbelief. She kept talking for nearly thirty minutes, and I was still so dazed that I was staring blankly at the sky until my sister poked me in the side.
"...Ah, sorry, Hyunseo. I was on the phone for a second..."
But when I looked over, my sister’s expression was far from normal. Her eyes were wide, her face set in a terrifyingly cold glare as she leaned in close to interrogate me.
"Who were you talking to for so long? Is it a girl? It's a girl, isn't it? Are you close? What's your relationship? How long have you known her? How old is she?"
"C-calm down, Hyunseo, it's just a parent of one of my students..."
No matter how hard I tried to explain, my sister stayed sulky and refused to even pretend to listen to me. In the end, I had to use my trump card to soothe her anger.
"...Th-then, when we get home, I'll do 'that' for you in the bath, so stop being mad...."
At that, she immediately turned her head, her eyes sparkling as she looked up at me.
"...Really?"
"Yeah, really...."
Only then did her anger melt away, and she spent the rest of the day giggling and enjoying our date. Once we got home, we went straight into the bathroom to bathe together. I had thought many times that we were too old to be bathing together, but I knew better than to say it out loud, as she would get furious. She clung to my back, rubbing her bottom against me and splashing water, laughing like a child. The scent of her fragrant shampoo from her wet hair tickled my nose.
After chatting and playing for a while, just as the heat began to make my head swim, she turned to me with a flushed face and whispered.
"...Now, do 'that' like you promised, Oppa."
"Yeah, o-okay...."
And about thirty minutes later.
Smack, smack, smack, smack, smack, smack, smack...
"...My little sister is the best, the prettiest in the whole world..."
"Haa.... haa.... do it... do it lower, lower.... haa-ah...."
In the steam-filled bathroom, she panted like a puppy, her tongue lolling out as she clung to me. Her breaths echoed off the tiled walls, making the atmosphere even more erotic. My palms were wet, making the skin of her buttocks stick to my hands with every strike. She gasped for air, as if she were on the verge of climaxing, her entire bottom flushed a deep, vibrant red.
When my arm grew tired and I started stroking her bottom rather than hitting it, she shivered, her back arching as she rolled her eyes toward the ceiling and let out a thin, high-pitched moan.
"Ooh... oh-gok... oh-go-gok... haa-ang.... right there, that feels so good..."
Only after I had stroked her soft, supple bottom countless times in the hot water, until she was nearly in a trance, did she finally feel satisfied. We lay down in bed together, her body pressed tightly against mine. She rubbed her cheek against mine and mumbled.
"...Goodnight, Oppa! Do your best tomorrow too!"
"Yeah, you too...."
I replied, completely exhausted, as I drifted off to sleep.