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It was pretty simple to understand. Two young and growing boys stuck at home in the summer, with nothing to ease their boredom besides annoying the living shit out of each other.
It was already nearly 34° Celsius, and it was only around 1 pm! Atsumu sulked his way down from his room, he had just finished his math homework… Who cares about numbers and division and multiplication or whatever anyways?!
He wanted to get some ice cream to eat, then chill with the fan on while watching TV! The fact that their mom made them do Kumon over the summer was… preposterous.
Osamu was in the living room, lazy and bored. When Atsumu saw Osamu, he whined. He came downstairs to cool down and here Osamu was, taking it all for himself!
“Samuuu~! Stop hogging the fan!” Atsumu tried to shove his twin away from the only fan in the house, but Osamu didn’t even budge. The younger twin sat right in front of it, letting the wind blow against his face. “Nuh-uh! You had it earlier you dummy!” Osamu snapped back at the boy. Atsumu stuck his tongue out at Osamu. “Well- Then I’m telling Mom!”
Osamu glared at his twin. “Mom’s not even home right now! Plus- Mom wouldn’t even listen to you! I’m her favorite child!” Atsumu pouted at that, before absolutely throwing himself at Osamu, making the boy fall into the couch as the two tiny kids wrestled around like it was something they knew how to do from instinct. Well… Maybe it’s wired into your brain, especially if you have a twin.
They always have a wrestling session nearly every day, so this wasn’t anything new at all.
They fought. Aggressively. They both tried to throw the other one under them, so they would have the upper hand. Atsumu growled lightly, aimlessly grabbing anything of Osamu. His arm, his hair, his ear, his- crotch? Osamu yelped at that, now trying to lodge the grip off of him.
Atsumu grinned at the expression, gripping tighter to toy with his twin.
“‘Tsumu- Stop that!” The younger twin sputtered, his demeanor seconds ago falling into this blushing mess. Atsumu cocked his head to the side, but eventually let go. “... Are you okay Samu?” Even though the two bicker and basically pull each other’s hair out, Atsumu wouldn’t want to actually hurt his twin.
“Y-yeah… That.. just.. felt weird.” Atsumu was under Osamu while the younger one was looming over him, a light canvas of pink all over his face. There was a small awkward silence for a tiny bit before Osamu spoke up. “‘Tsumu- C-can you do that again…?”
Atsumu looked extremely confused but still complied. Didn’t Osamu tell him to stop? Slowly, he reached for Osamu's crotch again, touching lightly. Osamu gave out a small noise at that, blushing all over his face now, even his ears were red.
“‘Tsumu- Wait- Let me try something-” Without a clear warning, Osamu snaked his tiny hand under him, and touched Atsumu at the same spot.
“Gchk-”
Atsumu couldn’t explain the feeling. Heaven? Bliss? Atsumu can’t find the right words.
“Ngh- Samu-!” Atsumu mewled, eyes widening at the feeling. “‘Tsumu… Keep touching me.” Osamu demanded, flimsy hands rubbing against Atsumu’s pants, trying to copy what the older twin was doing to him.
Atsumu frantically nodded, letting his hand roam free and do… whatever.
“Samu! I- Samu..!” Atsumu writhed under Osamu, gasping at the foreign sensation for the kid. “Feels- I-“ The older twin was lost for words, in his whole life, Atsumu never felt like this…
“‘Tsumu… Take off your pants and underwear…” Panting filled the room, their inexperienced bodies already craving for more. Atsumu didn’t even question Osamu, just did what the younger one ordered, like a dog following instructions.
As Atsumu took off his tiny shorts and underwear, Osamu watched while doing the same, leaving them both semi-naked from the waist down.
Osamu let out a small “Ahh…” at his twin. Atsumu stared at their tiny cocklets, eyes raking up and down. “Samu… My peepee hurts…” The younger one nodded in agreement, just staring at their bodies and comparing them.
“‘Tsumu.. Do you want to try something-..?” Osamu wasn’t really sure of what he was doing either, but it felt so… good. “What is it?”
The boy motioned to their cute little dicks, face blushing. “I- I wanna see how different you are to me ‘Tsumu!” Atsumu giggled but nodded.
“I trust Samu~!” Osamu gave him a cheeky smile. “And I trust ‘Tsumu with my whole life.” Osamu lowered his hips so their pelvises touched before the younger one rutted up and down. It was pure pleasure, so intense that there was really no way to explain how he feels.
Doing this relieved the pain in Osamu’s private part, and he bets it’s the same situation for Atsumu. Osamu wanted more friction, his body was unconsciously chasing for more as Atsumu made all these pretty sounds below him-
Was he feeling this way because of Atsumu? It was probably that. Who could resist such a cute twin that makes your life both interesting and miserable? The older twin gasped, hips buckling up to match up with Osamu. “Samu! S-stop- I’m going to p-pee-!” Atsumu squealed, stomach coiling with heat but his peepee felt like he really needed to go to the bathroom. “‘Tsumu… M-me too… Ngh-” Osamu paused, much to Atsumu’s dislike, and grabbed both of their cocklets together, shakily rubbing the tips of their private parts with his thumb, a little bit of… clearish fluid building up at the tips.
When Osamu flickered his eyes up to look at Atsumu, the younger felt his mouth go dry. Ever since they were born, the two had been inseparable, always depending on each other and always getting in trouble with each other. But now- This- Osamu can feel their bond get ever closer- As if they found a new side of their relationship as twins.
The boy under him was so damn pretty . Even though they were basically identical twins, Atsumu was somehow the prettier twin. He looked so… beautiful like this. “‘Tsumu,” Osamu stammered, speeding up his hand, the obscene noise of shlick filling up the room. “I love you- Feels so good-“
“Samu- Love you too- I love you- I’m peeing Samu- Ah!” Atsumu came with a loud cry, eyes nearly rolling back at his first experience of an orgasm. Osamu followed Atsumu suit, white fluids staining Atsumu’s t-shirt. “Ngh- ‘Tsumu~!”
The two stayed as they were, panting and basking in the small afterglow. Atsumu was the first to speak up. “Samu- W-why is it… white?” The older twin looked horrified. Osamu peered at the fluid, giving it a curious look. “Huh…” Osamu poked his fingers in the small puddle, scooping some up, and studied it. Without thinking, he brought his fingers to his mouth, giving the white stuff a quick lick.
Atsumu stared at him as if he just killed somebody. “Samu- What- That’s dirty!”
Osamu shook his head. “No. It’s… kind of sweet and salty.” He makes a small “Blegh” face.
“You try some,” Osamu said, inching his fingers closer to Atsumu’s face. The older twin hesitatingly opened his mouth, letting Osamu put his fingers inside his mouth.
Atsumu wrapped his mouth around the digits, sucking on them lightly, like a popsicle. Osamu felt his twin’s wet tongue swirl around his fingers, sucking off the fluid, pulling back with a pop . He made a face as well, grimacing. “That tastes weird!”
Osamu giggled at that, wiggling his fingers around in the air with a mocking expression on his face. “Ohohohoho… What if I force you to eat more ?” He teased, making Atsumu scowl at him. “Im going to beat you up if you do!” Osamu snickered. “You know you love me~ We should clean up before Mom gets back home though.”
“Stupid Samu.”
Osamu giggles again. “Dummy ‘Tsumu~… Do you want to do that again…?” Atsumu blinks at Osamu. “But I’m tiredddd Samuuuuu~!”
Osamu stepped a bit closer to his twin. “You won’t need to do anything.” The older twin rolled his eyes, not sure what Osamu wanted to do now. “Okay… fine.”
He grinned mischievously before crawling back to Atsumu, curiously flicking Atsumu’s right nipple. “W-what are you doing Samu?!”
“I- I want to try something… Trust me!” Osamu’s face inched closer to the left one as he continued to play with the right nipple with his fingers. Atsumu’s nipples were already kind of perky because of the cold wind blowing at them from the fan, and contrasting it to Osamu’s warm breath.
“Ah- Samu- W-Wait! Stop,” Atsumu writhed around again, limp cocklet twitching.
Osamu paid no attention to him, instead, gave the pinkish bud a kitten lick, causing Atsumu to jolt in surprise. Warmth engulfed Atsumu’s whole body, spreading like wildfire. “ Eek ! Samu! Feels- weird… S-Stawp~!” Being fueled by all the cute noises Atsumu was making, Osamu lightly bit on it, just experimenting around.
When the older twin let out a small whimper, Osamu stopped. “It doesn’t hurt right?” He asked, looking up at his brother worriedly. “N-No… More- Please Samu…” Osamu smiled, resuming what he was doing. Even though he had no experience, his passion made up for it.
Osamu can distinctly taste the honey body wash they share on Atsumu’s body, making Osamu get even more excited.
“S-Samu~ I-I’m going to pee again- Stop!!” Atsumu cried, eyes widening. “It’s okay ‘Tsumu! You can go…” That’s all the boy needed, as the older twin came again with a small wail, but nothing came out of his spent private part.
Osamu watched in fascination; Atsumu was so… reactive.
“Enh!! A-Ah… stawp-! Hurts now-“ Osamu quickly let go of his brother, checking him for anything that might be out of the ordinary. “Are you okay..?” Atsumu slowly nodded, eyes nearly glazed over. “Y-Yeah…” His voice was a little shaky as he came down from his high. “A-ah…? Nothing came out this time Samu…”
Osamu looks even more confused now. “Is there something wrong with your body then?” Atsumu was panting as he glared at Osamu. “This is all Samu’s fault!”
“Whoopies?” Atsumu lightly pushed Osamu off of him, cringing at the mess. “At least it didn’t get on the couch…” The younger muttered, knowing that no marks can be left on the couch or their Mom would kill them.
“... We can take a shower together though, we’re both dirty!” Atsumu offered. “Yeah… Let’s go.”