The Story of How Producing My Timid Older Sister Developed My Sexual Preferences

Chapter 026: (Sister) The Truth About Me Revealed

Right now, only Teru-kun’s gentle voice, his strong arms holding me, and his hand stroking my head are barely keeping me human.

A greedy, ugly creature like me should have just died when that incredible pleasure hit — my heart stopping right then would have been better.

I’d do anything for Teru-kun. If it makes him make that pained face, that face like he’s about to cry, I’ll blame everything on him.

I wanted to talk with him more, so I forced myself to heat up the bath and even wore embarrassing clothes just to keep him with me longer. I was so happy to hold hands again after so long that, even though I knew it was wrong, I wanted to keep holding on a little more. Even that feels like it’s turning into a lie, and it scares me.

The truth is, I also wanted to kiss Teru-kun. I got excited when I realized he was aroused by me. The ugly desires I had sealed away for seven years were about to overflow. And when Teru-kun trembled with that look of despair on his face… he looked so pitiful, so cute, so precious… the dam broke so easily, and everything flooded out like muddy waters.

Even then, while still making excuses, I became one with Teru-kun, but I drowned so deeply in my own shallow pleasure that I couldn’t even hear his precious voice anymore…

Now that I’ve shown him this ugly side of me, I should confess everything to Teru-kun and then disappear somewhere… It doesn’t matter what he thinks of me anymore. It’s all my fault.

Looking back now, maybe my life was already decided the day Teru-kun was born. Even though I was only three years old, I can still remember the day Teru-kun was born so clearly.

Mom called me an angel, but that’s wrong. The real angel is Teru-kun. She thanked Mom over and over for giving her such a cute little brother.

I had always received plenty from my parents. As a child who didn’t yet understand words, I didn’t know what the vague, formless thing they called “like” was. But the moment I touched his tiny hand, I understood. This is what it is. Before I knew it, tears were falling.

I now know the word “love.” People say love has no shape, but it does. Teru-kun himself is love.

I was told that Teru-kun and Mom couldn’t come home yet, and I cried loudly without stopping. Dad desperately pulled me away and took me home. I didn’t want to be separated from Teru-kun even for a moment.

After Teru-kun came home, I hated going to kindergarten — which I used to enjoy — more than anything. Every time the shuttle bus came, Mom got seriously angry at me for crying so much. But that’s how much I hated being apart from him.

So when I got home, I’d always stick to him. When Mom breastfed him, I’d say “No fair! I want to do it too!” and pretend to feed him. Mom would laugh and say “Big sister can’t produce milk yet,” but I was seriously jealous of her.

When I entered elementary school and got my own room, I started sleeping with Teru-kun every day. Those were happy times. I hated school because it separated us, but when I hugged him while sleeping, I could always do my best.

But… yes, it was when Teru-kun was in third grade and I was in sixth. I committed a mistake that should never have been committed. I dirtied him myself. The Teru-kun I loved and cherished so much.

At school, we learned how babies are made. I didn’t really understand it at first, but I overheard the boys in class talking excitedly about dirty things and gained that knowledge.

After that, Teru-kun’s little penis — which I washed for him every day — started looking special to me, and I noticed that my own place would get wet every time I washed him.

…It comes out to make it easier to create a baby… I want Teru-kun’s baby… That’s what I thought immediately.

After Teru-kun fell asleep next to me, I’d pull down his pants and touch his penis. When I checked and found my own place wet, a sharp, aching pleasure ran through me.

I knew that if I made a baby now, Mom and Dad would get angry. So I wouldn’t do that. But just practicing — touching Teru-kun’s penis while making myself wetter… I didn’t know what it was called back then, but that was when I first learned about masturbation.

After that, the acts escalated every night. His penis was so cute that I started putting it in my mouth. Seeing it get hard, I convinced myself that Teru-kun also wanted to make a baby, and I got more and more excited. My hand and mouth movements grew intense, and Teru-kun woke up. Even so, I couldn’t stop. I straddled the anxious-looking Teru-kun who looked up at me——

‘It’s okay. It’s not scary. Big sister will make you feel good. You want a baby too, right Teru-kun?’

And then——

“Are you okay? Sis, have you stopped crying?”

“I’m sowwy… This isn’t like big sister at all… uuu…”

“You’re still my sister. You’ve always been my sister.”

“No I’m not… uuu, please listen… what I did to you, Teru-kun… uuu…”

“…I understand. I’ll listen. Take your time.”

“Before your accident, Teru-kun… when we were sleeping together…”

——I forcibly inserted Teru-kun’s into me. I don’t remember what face he made or what he said at that time. The cowardly me probably erased it from my own memory.

The next day, pure-hearted Teru-kun told Mom: “Sis might have a baby, so please take her to the hospital.” Not a single ounce of resentment toward Teru-kun appeared in me. Instead, I even felt joy at how desperately worried he was about me.

When Mom heard the reason from Teru-kun, she slapped my cheek. Tears flowed from my burning cheek as she yelled at me and calmly explained what I had done socially and ethically. Or maybe I calmed down while listening. So what? What’s wrong with that? I didn’t say it out loud, but it must have shown on my face. Mom forbade us from sleeping together or playing alone.

I couldn’t forgive her. For separating me from Teru-kun. That night, alone in my futon, I couldn’t sleep. Until the sun rose, I cursed Mom inside the futon all by myself…

After school, I would immediately grab Teru-kun’s hand and head home. I stuffed my entire piggy bank into my bag, and together with Teru-kun — who still wasn’t used to riding a bike — we headed for Grandma’s house.

‘Teru-kun, hurry! It’s getting dark!’

‘Wait! Sis, you’re too fast!’

On the slope leading to the station. Where the narrow sidewalk ended and the road curved sharply — that’s where the accident happened. I think it was the moment Teru-kun went over the curb onto the road. I heard his loud voice and turned around.

The white truck hitting him. Teru-kun’s body slamming into the ground in slow motion. The uncle getting out of the truck. The dark red liquid flowing on the asphalt. The taste of blood in my mouth, my throat hurting like it was tearing.

The uncle ran to Teru-kun, looked back and forth between us, and took out his phone. My ears gradually started working again… the sound of cars coming from the opposite direction…

Teru-kun died… I have to follow him right away… or we’ll be separated over there too…

I immediately ran toward the car coming from the opposite lane.

Just before I could cross the line, a strong force grabbed my arm and threw me to the ground… After that, I don’t remember anything until Dad came to the hospital and told me Teru-kun was alive.

Mom shouted in frustration at me because my throat hurt and I couldn’t speak. Teru-kun wouldn’t wake up. I didn’t go to school and just curled up in my room.

During the three months until Teru-kun woke up, our family fell apart. Mom never gave up and kept worrying about him. Dad grew haggard from the worry over the huge medical bills while desperately pursuing compensation from the driver. If Teru-kun wasn’t going to wake up, there was no longer any reason for me to stay in this world…

But he woke up. His body couldn’t move at first because he had been sleeping so long, but he had no lasting disabilities and was healthy. However… he had lost his memories. He remembered the faces and names of family and friends, but he was diagnosed with retrograde amnesia — unable to recall past events.

It was heartbreaking that all those happy memories had disappeared from inside Teru-kun, but as long as he was alive, that was enough. I decided I wouldn’t ask for anything more. As long as I could live in this world with Teru-kun, that was enough. I really thought that was enough… but why… did I start wanting to talk with him more? Why did I become greedy and want to hold his hand again…? I’m sorry… I’m so sorry——

“——I’m sowwyyy! It’s because I’m weeeird! Hit me! Get angry at meee!”

“…”

“I even broke the family apart! I’m sowwyyy! Please don’t forgive me! Uwaaaaaaaaah!!!”

“C-Calm down, Sis…”

Teru-kun gently strokes my hair. Please don’t spoil such an ugly creature… I want to disappear right now…

“I don’t know what to say, but… right now, my feelings are… probably happy ones… I’m feeling joy…”

Why? After hearing all that, why do you feel that way? I don’t understand… I want you to punish me… Please, Teru-kun… please…

Chapter 027: (Sister) Accepting All of My Sister Except…*

“I don’t know what to say, but… right now, my feelings are… probably happy ones… I’m feeling joy…”

I said it because I genuinely didn’t know what else to say. My sister immediately started crying even harder. After hearing everything, my mind was a complete mess.

I knew I had lost my memories in the accident, but I had never heard the full background…

There were many things I wanted to say, but right now I focused entirely on stopping my sister from crying. This was the first time I’d ever seen her cry with such loud, broken sobs. My chest felt tight — I was about to cry too.

I summarized what I’d heard, recalled the part that shocked me the most, and spoke honestly.

“Listen, Sis. Right now… I’m just so relieved that you didn’t die. My head is full of that. And… knowing that you loved me that much makes me really happy.”

“No, stop,” my sister wailed. I ignored her and kept going.

“And the accident… it was my fault for falling over. I feel bad for the driver too… Honestly, I’m just grateful he saved you. I want to go thank him and repay him someday. I really mean it.”

She kept shaking her head, saying “That’s not it.” I think my chest was getting covered in her snot and tears…

But I’m truly glad. We avoided the worst possible ending… If Sis had died… I probably…

I can only feel gratitude toward the person in the accident. If there was a Romeo and Juliet who died for such a stupid reason, Shakespeare would probably throw the manuscript away and wipe his ass with it.

“Um… and about what you did, Sis… You’re not a bad person. If someone tried to separate us now, I might do something crazy too… You were pretty wild, huh?”

“That’s not true… It’s because I had those weird feelings for you, uuu…”

“Then we’re the same right now. I wanted to do lewd things with you so badly I couldn’t stand it. I guess siblings really are alike, even if we look so different.”

“No! I’m…”

“Are you going to throw those feelings away? I want you to keep them. I want to feel the same way.”

“I…”

Yes! She’s calming down! As expected, my sister is ridiculously easy!

Now I just need to keep pushing like usual without overthinking. It’s a little embarrassing though…

“Is it wrong for me to feel this way? Is it weird? Is it wrong that I want to kiss you, fuck you, and jerk off while looking at you? Can’t you just leave me alone? If you feel the same, is it wrong for me to be happy about that? You’re always thinking about me, doing things for me, even when I say horrible things. You’re so beautiful, have such an erotic body, you’re kind, and you can do anything. There’s no reason not to like you. Actually, I do like you, Sis. As a woman. Is that weird? Is it wrong? You don’t have the right to deny me, do you?”

“Wha—!? Like… you mean you li——”

Whoa! My dick was still inside her… It just squeezed tight.

For now, I didn’t give her any time to make excuses.

“Also, when you started crying earlier… Wait, I vaguely remembered something when I put it in. I thought maybe you took my virginity before. Then when you cried, it all came back clearly. That insanely arousing night that appeared in my dream recently — I had completely forgotten. You licking my cock was super erotic. I think I was really happy and begging you to do more… Wait, actually, before that I had noticed you secretly doing things to me while I was sleeping…”

“St-Stop iiit!!”

“I won’t! Yeah, that’s right! I was always pretending to sleep and letting it happen! It felt so good I came multiple times, but I hadn’t gone through puberty yet… Damn, it’s all coming back! Just how much do you like me, Sis!? Amazing. It’s amazing! So my feelings weren’t wrong! I like you too! What about you, Sis? Do you still like me right now, this very moment? The same as before? Tell me honestly.”

“Uuu… I love you so much… No matter what I do, I can’t get rid of it!”

“Then isn’t that enough? This is the best feeling! For now, this is more than enough. Kiss me? If you like me.”

“Like this… I——”

“Can’t you? I’m about to pull out though?”

“Uuuu… Nooo…”

“Fiiiive… fouuur… threeee!?”

It happened faster than I expected. The moment my cock slipped out with a chupo, Sis threw herself at my lips. I could taste the salt from her tears and snot… I might be the first person in human history to hear such a heavy story while still connected during sex.

If she was this easy, she should have talked to me sooner… No, that’s not right. It’s because of everything that happened in these past few days. They were precious. All the important memories with Sis that have been slowly coming back. Without them, I wouldn’t have been able to filter through the mess in her heart.

There are probably still things I haven’t remembered, and Sis still hasn’t fully accepted everything — she’s holding onto a lot. But I think it’ll be fine. The fun days ahead and this ridiculously easy sister don’t worry me at all.

By the way, the “fun days ahead” obviously include a lot of erotic stuff too.

I’ll accept all of Sis, but she’s going to be punished for hiding the fact that she appeared in my dreams and made me have wet dreams, for stealing my virginity, and for toying with me so much. The second one is a bit of a stretch, but… I suffered a lot and even got depressed, so it’s fine. I hold grudges.

“Nnpuh… Sis, wait a sec. Should we sleep soon? It’s already 2 AM.”

“Nooo…”

How greedy can she be…? You’d never think she had a face like she wanted to die from guilt just a moment ago…

“Sleep together? Then it’s okay, right?”

“…Yeah… Then… move back a little…”

“Like this? Nn!?”

The moment my face sank into her soft breasts, she hugged me and rolled us sideways.

Usually the one comforting should be the one hugging, but… it’s incredibly soft and smells nice. That’s right — I was planning to live here forever earlier. I’m home.

“Good night… Sis.”

“Good night… I love you so much…”

I love you too… I was going to say it, but her breasts felt so good that an insane wave of sleepiness hit me.

Of course I’m exhausted today. Way too many things happened. Family stuff and everything else can wait until tomorrow. Let’s do our best tomorrow. Heaven was this close all along———

“…What’s ‘shiko’…?”

“…”

“Teru-kun… what’s ‘shiko’?”

“…”

“Hey, did you fall asleep? What’s ‘shiko’?”

“…Shut up. Shiko shiko shiko shiko… What the hell is shiko?”

“Sorry… but you said it earlier and I didn’t understand only that part… ‘jerk off while looking at you’…”

“Shiko means… masturbation! Good night! Don’t talk to me anymore!”

“…That means… while looking at me…”

“…”

“Uuu… You called me a sow… So that’s what you meant…”

“…”

“Teru-kun, you said ‘sow’ earlier… I remembered… You did say it, right?”

“I didn’t!”

“You diiid!”

“I said I didn’t!”

“You diiid…”

“…”

“…Teru-kun… you’re angryyy…”

“! I don’t remember! Even if I said it! I didn’t mean it! It was just the mood! The excitement of the moment! Anyway… I don’t think that at all! And I’m not angry! If you say one more word, you’re sleeping in your own room. That’s it.”

“Uuuu…”

I really hate this! I seriously hate this annoying, persistent side of Sis! This part doesn’t resemble me at all.

I fell asleep in 2 seconds.

Chapter 028: My Sister is Still Full of Mysteries

An unfamiliar alarm is ringing loudly. It’s also too bright. I’m wrapped in such a nice scent and sleeping so comfortably — don’t disturb me… Wait, I’m completely naked… That’s right…

I smacked the alarm clock next to the pillow and jumped out of bed. The unfamiliar room lit by morning sunlight brought back yesterday’s memories even more vividly.

“…I see.”

…The joy of having made love with my sister and the anxiety of the mountain of problems ahead are coexisting in my brain, splitting between the right and left hemispheres.

“Shit… What the hell is this emotion…?”

For now, I buried my face in the pillow and took a deep breath. Aah, Sis’s scent~ — mixed with the smell of her hair product. Come to think of it, I didn’t properly bathe yesterday. Though she did wash my dick for me…

This wasn’t the time to be excited. Reluctantly, I got out of bed. Since I was dragged into her room naked last night, I didn’t have any clothes. Wait — there they were. At the foot of the bed. My loungewear, neatly folded and freshly washed.

“Sis really is…”

While putting on the kindness of my sister, I looked around her mysterious room. There were no stuffed animals, let alone idol or anime posters. The most noticeable thing was this huge bookshelf. It was packed full of various qualification and certification study guides.

“She studies this much…? What does she plan to become… Oh right…”

On the wall that was too dark to see last night hung many framed photos. They were all family photos.

There were photos of all four of us, photos of Sis and me, photos of just me, photos of Sis and me, me, me, me and Sis, me, me, me and Sis, me and Sis, me, me…

The ratio was weird. The frames were arranged with perfect balance and stylish taste, yet their contents showed zero sense. It was honestly a little scary… The love for me was far beyond what I imagined. I might have opened Pandora’s box…

“Right… I need to buy the pill.”

I left my sister’s room as if escaping and forcefully opened the living room door.

“Good morning! Sis! Um…”

“…”

My sister had returned to her usual baggy, frumpy outfit. Though her hair and eyebrows looked beautiful compared to before. No… that’s not important right now.

“Are you listening? Why won’t you face me?”

“…Morning.”

Still facing the complete opposite direction, she muttered something and started walking toward the kitchen.

Hoooh, so that’s the attitude you’re going with. How troublesome~

I think she’s just embarrassed, but I have no intention of going back to square one. I chased after her back.

“Sis… My dick hurts… Because you forced it in yesterday…”

“!? I-I didn’t!”

“You forgot…? Even though it’s such an important memory… So mean… uuu.”

“Th-That’s not it!”

“You only see me as a—”

“Nooo! That’s not true!”

“Your voice is loud! I’m joking. You’re always this troublesome, so I was just imitating you.”

“Nooo…”

“More importantly, Sis, about contraception…”

“Uuu… I looked up a hospital earlier, so I’ll go today…”

Her cheeks turned pink, probably remembering yesterday. Good. I was a little worried after seeing those photos that she might say something like “Let’s have the baby!”

“I see. Thank you…”

“…Yeah.”

Ah… Damn. My bad habit came out again.

Just getting the pill probably involves an examination, right? Will she have to sit in that weird forced M-shaped leg spread chair and have some greasy old man look at Sis’s pussy — which even I haven’t seen properly yet…? I really hate that thought. It might be stupid to think this, but I hate it so much. What should I do…

“Um… Is there a hospital with a female doctor?”

“…? I’ll go to one run by a woman.”

“I see… Never mind then. I’ll go take a bath.”

Thank god!!!! I was about to get so depressed I’d skip school.

“Ah, um, Teru-kun! That…”

“What?”

“Um… that… If you… shiko… then…”

“Hm…? Shiko?”

“So, um… you know… If you shiko and cum, please… do it in a tissue or something… It would help… uuu.”

Just saying “shiko” doesn’t explain anything! Come to think of it, she was going on about something last night too!!

“!? Why are you bringing that up right now!?”

“The T-shirt you gave me… I couldn’t clean it properly… If it gets on your underwear next time, I’ll wash it for you…”

This girl! Are you trying to humiliate me!? She’s definitely noticed the smell and figured out everything I’ve done!

“Haa? I basically don’t cum in my underwear! I know that already!”

“B-But last time with yours… When I washed it with hot water it got hard…”

I didn’t know that… Damn it!

“It’s all your fault!! How dare you say that!”

“I-I’m sorryyy!”

“From now on I won’t cum in tissues or underwear!! I’ll cum all inside Sis! Everything!”

“Th-That kind of thing…”

The moment her face turned red, she pressed her hands against her lower belly and rubbed her thighs together shyly.

I didn’t say I’d cum inside, you closet pervert!

“No, wait — I’m not going to jerk off anymore! Do you know why? Because Sis is going to shiko shiko for me instead! And it’s not ‘shiko’, it’s ‘shiko shiko’! ‘Shiko’ is the verb! Whatever, it doesn’t matter!”

“Uuu…”

“What’s your answer?”

“…Yes…”

She’s clearly looking forward to it while pretending to hate it. How fake. Stealing my virginity is a heavy sin. (Though I’m happy about it.)

“Also, Sis, your moaning voice is way too loud.”

“!?!!?… Stop iiiit!!”

“It’s seriously dangerous. You’re usually so quiet. Mom will find out easily.”

“Stoooop!! I won’t do it when Mom’s home…”

“I wonder if you can hold back~ Especially now that you’ve remembered you’re a pervert, Sis~”

“Nooo! I can hold it! You’re always so mean…”

“You’re the one who started the fight.”

“I didn’t mean to…”

“Anyway, I’m going to take a shower!”

After my successful counterattack, I took a shower. Just imagining our future life from Sis’s reactions earlier was enough to make me hard.

Remembering that my pure and quiet-looking sister was actually a massive perverted masochistic brat put me in a strange mood.

I wonder if she’s masturbating right now… If so, how often…? Does she use toys or something…? No good, my imagination won’t stop.

In the back of my head, the sexual harassment old man is peeking at me. He looks very interested. When I told him I’d let him take the cockpit next time, he said he’d quickly finish writing the interview script for Sis and disappeared. I’ll leave it to him.

What I need to think about is family matters.

Of course, our relationship must never be discovered. If it is, we’ll probably both get beaten and separated.

What concerns me is what Sis said yesterday about “breaking the family apart.” I want to tell her it’s not her fault.

I don’t know the reason for the divorce. But Mom is a lot like me — a woman born in the Year of the Snake who holds deep grudges. I can roughly guess it was pent-up anger that finally exploded during a fight… but I need to figure out how to ask about the reason. Well, I’ll think about it slowly.

I turned off the shower and left the bathroom.

When I returned to the kitchen, Sis, who was standing at the counter, asked:

“I’m making onigiri and rolled omelette — do you want them in a bento?”

“Sorry, I didn’t tell you. School ends at noon today until summer break starts. What about you?”

“I still have tests, so I have school until the end of the month… Do you want to eat now? Or when you come home?”

“I see. I’ll eat now, thanks. Since you have tests, does that mean we can’t go shopping on weekends?”

“I-It’s fine! Totally… I can go…”

“Then let’s go on Saturday. You study a lot, don’t you? You had so many qualification books — what do you want to be in the future?”

I’ve never heard about my sister’s future dreams, so I was curious. With that many books, I couldn’t tell what kind of job she was aiming for.

“That’s… a secret…”

“Huh? Why? What’s the point of hiding it?”

“It’s… definitely a secret…”

I can’t understand why she’d hide it. When she keeps it this secret, it only makes me want to find out even more.

Oh, the sexual harassment old man threw a paper airplane with a script. Let’s see…

“Ask her future dream or her cup size. Make her answer one.”

“Wh-Why!? Nooo…”

“Hurry~ I’m gonna be late~”

“I-I won’t say…”

“Hmm, about my first time you sto——”

“Waaaah! I-It’s… H cup…”

…D, E, F, G, H. Hmm. Not bad at all, is it? I think I’m salivating more than when I look at the rolled omelette.

“…”

“Say something!”

“…Pervert.”

“!? Why…?”

Anyway, I need to get to school soon. There’s no end to teasing Sis.

“Well, I’m heading out. Thanks for the food!”

“Uuu… Have a good day…”

“See you later.”

As I was putting on my loafers at the entrance, Sis for some reason followed and stood behind me.

“What’s up?”

“H-Have a good day…”

“Yeah… See you.”

I already said that, I thought, but I replied anyway.

“…Do it.”

“Huh? What?”

She fidgeted restlessly like she needed to pee and muttered something. Why is her face red? Come to think of it, there’s a fetish for girls holding their pee…

“…Chu… Kiss… I want one…”

“…!?”

…Gah! It felt like I took a body blow the moment I breathed in with my guard down.

I feel like I could push her down right here and collapse. Maybe it’s fine to collapse… Maybe I should just skip school today…?

No, bad idea. I can easily imagine sinking deeper and deeper. I’d become a truant. Summer break is almost here — endure it, Terumi!

“Fuu… fuu… Come here…”

“Y-Yes.”

I took one step forward. Sis bent down to my height with her knees together, hands on her thighs. She squeezed her eyes shut and slightly puckered her plump lips.

Damn it! I desperately clinched, but she’s throwing short body blows!

…Chu. I only lightly touched her lips. Any more than this and I really won’t go to school.

“W-Well, I’m off!!”

Without waiting for a reply or looking back, I dashed out the door.

Is this going to happen every morning…? Will my sanity hold…?

For now, I added “train abs” to my summer goals and headed to school.

My sister’s mysteries only keep deepening. The thing I need to investigate as soon as possible is… that pussy.

I’ve never experienced such an obscene cunt before. And I’ve only been with four people including Sis…

I need to research it thoroughly. Will Mom come home today? I forgot to ask. I prayed “Don’t come home, you hag” while walking down the hot road.