The First Union
Cold sweat began beading across my entire body from the tension. So this is it. We’re really doing it.
Slowly, ever so slowly, I moved my hips, and my body gradually disappeared into my sister’s. Her lower lips parted and clenched tightly around my glans. “Hnnngh! Haah…”
“If it hurts too much, should I pull out?”
Maybe I should have spent more time on foreplay before trying to push in. Yunseo looked like she was struggling; even with just the tip inside, she was whimpering sharply and clutching the bedsheets.
“Haa, haa… No. Haa, haa… Just stay still for now. Don’t move.”
Following her request, I stopped with only about half my glans inside. I stayed as still as possible so she could adjust to me—slowly, carefully.
“Haa… So this is what a cock feels like.”
“Yeah. This is a cock.”
One made only for her. One that only looked at her.
“Hey, you know… chickens…”
“Mm?”
“Chickens probably feel like this every time they lay an egg. It’s like they’re pushing it out of their pussies. If you have any conscience, you should stop eating eggs. Hnn, hnn…”
“Okay. I won’t eat them.”
“I-I won’t eat them anymore either. Egg rolls are such a bad food. Haa, haa…”
Yunseo glanced down at where our bodies were joined. Curious myself, I looked between her legs to see how we were connected. Her usually neat, straight outer lips were now spread wide, swallowing my glans. They were already flushed red; she might need an ice pack later.
Can I… keep going? She looked like she was in so much pain. Sweat had gathered on her forehead, so I quickly wiped it away with the back of my hand.
“You okay?”
“Huu, huu…”
“Should I move more, or wait a bit longer?”
“No, I can do it. Just… move as slowly as possible. Don’t go fast.”
“If it’s too hard, we can stop and try again next time. You look like you’re really struggling right now.”
Tears welled up in her eyes, threatening to spill down her cheeks at any moment. It hurt to see that pretty face twisting in pain because of me.
“If we stop now, will your cock get smaller? I-I’m fine, so just move a little. Just a little.”
“Got it. Just a little, then.”
“Huu, huu…”
When I started moving again, her body trembled. I pushed my hips forward as slowly as I could, being as considerate as possible. Our bodies ground together like millstones. Her inner lips were gradually pulled inward with my movement.
“Hnnngh, huu, haa, haa…”
Her moans echoed through my room. Guilt at hurting the woman I loved and the thrill of conquering her body—two incompatible emotions churned violently in my head.
Finally, my glans went all the way in. Yunseo, who had been clawing and pinching the mattress, switched targets to my back. Ow. She grabbed onto me tightly and dug her nails in. I could feel my skin being scratched. If we weren’t careful, both of us might end up bleeding.
“M-Minjun…”
“Yeah?”
“Is it okay… doing this with your sister?”
“More than okay.”
“Haa, haa… But it’s so big. It feels like I’m giving birth. Still… we managed to get it all the way in. Us.”
“It’s not all the way in yet…”
“What? Then how much is left?”
“Just the glans went in.”
“Haa… Hey, why are you so big? Are you trying to kill someone?”
“…Sorry.”
“I thought we were done, but you’re saying it’s still not all in.”
“That’s why I said we should take a break.”
“Who stops halfway through? If we started, we have to finish.”
“You’re struggling so much, though.”
“Then you shouldn’t have been born this big.”
We were at a stalemate. Staying hunched over like this was uncomfortable. A drop of cold sweat fell from my forehead onto her chest.
“Or… we could do more foreplay. So your body can relax.”
“Would that… make it hurt less? I’m already… pretty wet, though.”
“There’s nothing else we can do right now. Try to relax as much as you can.”
“Okay.”
Yunseo closed her eyes and puckered her lips. She stuck out her tongue and reached up to play with my ear. I racked my brain trying to figure out where and how to touch her to make her more aroused.
“You… move another centimeter.”
Since I kept licking her sensitive ear, she seemed to be feeling a bit better. Following her words, I lowered my hips slightly.
“Hnnngh! Haa, haa… Hey, was that really only one centimeter?”
She clawed at my back again. I was already dreading how much it would sting in the shower later.
“Don’t worry. I really only moved a tiny bit.”
Honestly, I wasn’t sure. I wasn’t a machine—how could I measure it that precisely?
“It feels like… a lot went in. Okay, fine. Keep going. I can still handle it.”
Listening to her, I continued moving my hips. Something caught at the tip of my glans.
“……Yunseo.”
“……Yeah.”
She seemed to have felt it too—why I had stopped.
“I’m going to keep going.”
“Okay. But…”
“Yeah?”
“Hold my hand. Hold it tight.”
Our hands intertwined, fingers locking together. At the same moment—push! I thrust my hips forward into her.
“Hnnngh!”
Yunseo cried out, probably to endure the pain of her hymen breaking. Holding hands, the siblings began having sex. No one had taught us, and neither of us had done it before, but once the chance to be with the woman I loved arrived, my body moved on instinct—awkwardly, roughly—filling her with myself.
“Hnnk, haah, haah, haah…”
The pressure of pushing into her tight walls was intense. Her insides were warm and squeezed me tightly. Even with the condom on, the pleasure bubbling up and threatening to boil over in my head spread through my lower body.
“I-I… kiss me, quick.”
Yunseo looked up at me. Still moving my hips, I pressed my lips to hers. Our bodies rocked back and forth, making our faces shake too, but I couldn’t stop. Even while kissing, our foreheads and noses kept bumping. We’d pull apart to breathe only to desperately press together again.
“M-Minjun… Haa, haa…”
“Huu, huu, yeah…”
I’d thought I had good stamina, but the different muscles I was using made my breathing ragged too.
“D-Does it… taste good?”
“Best thing Mom’s ever made. What about you?”
“Me too… Your cock tastes amazing.”
Squelch, squelch. Glorp, glorp. Yunseo was very wet. Every time I thrust in, her juices made an obscene sound. Blood, sweat, saliva, and all our lust mixed together, the essence of our pleasure churning between our legs.
“Haa, haa… I have to love you forever. If you look at another woman, I’ll kill her. You’re mine.”
“Haa, haa… Don’t worry. I’ll only ever love you. You have to… haa… only love me too.”
I was reaching my limit. I wanted to last longer for her sake, but the overwhelming pleasure made it impossible to hold back.
“Yunseo, I…”
In the end, I shamefully confessed my climax to her. Sorry I couldn’t satisfy her more. Sorry I couldn’t hold on because it felt too good.
“It’s okay… I’m… haa, haa… I’m close too.”
Yunseo seemed to be approaching her own peak as she squeezed my hand with all her strength. Thrust, thrust. Squelch, squelch. I kept bucking my hips toward her. It felt like my entire mind was being sucked toward my cock, drawn into her body.
“Hnnk… Hnnngh.”
“Hnnngh! Haaang!”
With completely opposite reactions, we reached the end of our sex. While I collapsed toward her as I came, she trembled and cried out loudly in pleasure.
“Haa, haa, haa…”
I rolled onto my side next to her, and my cock slipped out. I shouldn’t be collapsing so weakly like this. I wanted to praise her, tell her how happy I was to spend this time with her, gently stroke her hair, kiss her forehead—there were dozens of things I’d resolved to do for her, but unfortunately, I had no strength left in my body. All I could manage was reaching out to caress her cheek.
“Haa, haa…”
Yunseo looked exhausted too, panting beside me.
“We… really did it all the way.”
“……Yeah.”
I barely managed to turn my head toward her. When I held out my arm, she grabbed it. “You’re sweating a lot.”
“You too.”
She wiped my forehead with the back of her hand. Sticky cold sweat came off on her skin.
“I didn’t say anything weird, did I?”
“Something about not eating eggs. The chicken farm’s gonna come after you.”
Smack. When I pressed my lips to her forehead, it tasted salty from all the sweat. Her hair kept trying to get in my mouth, so I brushed it behind her ear.
“You could’ve just ignored it. Why’d you have to—”
“Sorry. You were just too cute. Aaaah.”
“What’s wrong?”
“My back… Check my back. See if I’m bleeding.”
Now that the excitement had faded, the stinging pain was setting in. Next time, I’d have to tell her to cut her nails first.
“You’re not bleeding… but it’s all red.”
“Are you okay?”
“I’m fine for now, but… I think I’ll be dying when I wake up. Hey, the condom.”
“Oh, right.”
It felt strange seeing my cum contained in the condom instead of splattered on tissues like usual. When I pulled it off, it glistened with the fluids that had come out of her. Looking at it made me realize what we siblings had just done.
“This red stuff… is that my blood?”
“Yeah.”
“I thought if my hymen tore, blood would gush out, but it didn’t. If it had, I probably would’ve passed out from blood loss halfway through.”
Everyone was different, but Yunseo had only a few drops of blood.
“Then I would’ve had to carry your naked body to the hospital. The perpetrator and the guardian would be the same person.”
She chuckled at that and smiled. I smiled back, happy to see her like that.