By Zephyria 
A cock too thick to be fully enclosed by a single hand thrust rapidly back and forth through the entrance. His consciousness was dizzy enough from the conflicting sensations scrambling through his brain, yet the cock stirring below showed no sign of slowing down. Whenever a pain like a direct blow to the lower abdomen surged up, a thrilling stimulation followed, as if encouraging it.
Under the rough thrusting that crushed the sensitive spots, his own erect cock shook frantically and slapped against Tae-un’s stomach. Tae-un licked his lips and whispered. Despite his heavy breathing, a bright smile played on his face.
“Hyung, you’re hard.”
“I—I am too, ah… ahh! Haa! Ah!”
Cheeks that had been pale with pain were now flushed red. Kim Si-baek couldn’t tell if the distortion of his face was due to the pain still surging from below or the onslaught of pleasure.
A large hand descended, groping Kim Si-baek’s convulsing thighs and buttocks, and fondled the joined area. Blood stained the fingertips that toyed with the tightly stretched hole. As if it were divine nectar, Tae-un licked that blood sweetly.
“Haa, Hyung. It’s so hot inside, and it tightens so much… ah, fuck.”
“Nng! Hah, ahh!”
“Does it hurt more, whew. Or does it feel better?”
Even while asking such a question, the movement of his hips didn’t slacken in the slightest. Kim Si-baek, barely holding on by gripping the sheets as his body was shoved upward, groaned like a scream.
“I don’t… know… hah, ack! Please, slow down…”
“Okay.”
Contrary to his compliant answer, Tae-un shrugged off the gown that hung clumsily from his shoulders. Before the gown could even hit the floor beside the bed, he pushed Kim Si-baek’s thighs up. His buttocks lifted slightly into the air, only to be slammed back down against the mattress by a force he couldn’t withstand.
The sound of thighs and buttocks colliding echoed through the room repeatedly, like the loud popping of a full balloon. With every violent thrust, the bed creaked precariously as if chased by the momentum. Absurd thoughts crossed his mind—that the bed legs might break, or that the internal organs receiving him might be bruised.
No, was that an absurd thought? Or a stupid one? He didn’t even know. He couldn’t maintain a proper train of thought. Even the fleeting remnants of reflection were quickly demolished by the extreme stimulation stabbing into him from below.
“Ha-heuu! Too… too much… hugh!”
The sensation of being rammed was overwhelming. His lower abdomen burned with a searing ache from the impact, like a piece of iron being driven into the soft, convulsing walls of his interior. As pressure pounded up toward his chest, a dry heave bubbled in his throat. It felt as if not just the space between his buttocks, but his entire body had become a hole to receive him.
When had he let go of the sheets? The realization that there was nothing for his sweat-slicked fingers to grip was slower than the speed at which his body was being pushed upward, wrinkling the sheets.
His helplessly flailing hand was caught by Tae-un. Even in the darkness, Tae-un bared his white teeth and bit down hard on his finger.
“Auk!”
A sharp pain surged. Tae-un chewed on the finger enough to leave teeth marks on the struggling digit, then yanked Kim Si-baek’s pushed-up shoulder forward. With that momentum, the thick cock, which had slipped out slightly, changed angle and plunged deep inside. Kim Si-baek’s back arched violently as an unexpected spot was pierced.
Pulling him close, Tae-un bent his waist and hugged Kim Si-baek’s shoulders. Hot, ragged breaths left a trail of kisses on his forehead and cheeks. As the heavy weight of the other man pressed down from above, his already labored breathing became as stifling as if a boulder had been placed on his chest.
Despite the suffocating weight, a sense of stability followed. Kim Si-baek clung to his shoulders and back with trembling arms. Holding him tightly, Tae-un slowly rotated his hips. As soft stimulation replaced the hypersensitive shocks that had been battering the inner walls, the cock buried deep inside felt even more vivid.
He felt as if he could sense the very shape of the cock as it rubbed slowly, pressing against the sticky inner walls that clung to it incessantly after thrusting shallowly—barely the length of a finger joint. The flesh walls swallowing him were likely stretched to that exact shape.
The thought made his mind go hazy, yet dizzyingly hot. Tae-un pressed his lips close to his ear, licking along the curve of the outer ear before poking his tongue inside.
“Hyung, do you like it better when I fuck you fast like before, or slow like this? Un-i’s cute cock is on standby for you.”
Cute…
Kim Si-baek, who had never once doubted Tae-un’s cuteness since meeting him at nineteen, felt a profound sense of skepticism for the first time. The weapon that had carved its way through raw flesh was cute… But then he remembered that he was the one who said it was okay to tear, so he simply gasped for air and scratched Tae-un’s shoulder.
“Do it… cutely…”
Tae-un let out a low, quiet laugh. His hips jerked back, and then he began to slam into him violently, as if the previous looseness had never existed. Without reason or restraint, as if this were the only act he knew, the beast-like, brutal movement of his hips began to stir Kim Si-baek once more with violent pleasure.
At Tae-un’s “cute” behavior, his melting consciousness flickered white again. He, too, was left with nothing but animal instinct, scratching at Tae-un’s back and shoulders and letting out groans that sounded like screams of pleasure.
“Ahh! Ah, aaah!”
Even without being touched, his erect, shaking cock spurted viscous fluid in surges. Tae-un, groaning deeply with a furrowed brow, bit hard into the nape of Kim Si-baek’s neck. The flesh walls, which had contracted sharply due to ejaculation, tightened instantly upon feeling the pain, and he felt himself becoming drenched from deep within.
“Whew…”
Tae-un, who had held Kim Si-baek in his arms until the tremors of ejaculation subsided, caught his breath and lifted his face from the nape of his neck. Kim Si-baek let out a low moan and let his strengthless hand flop onto the bed. He felt the sensation of his sweat-soaked neck being licked. In his daze, he wondered if what was flowing from the bitten skin was sweat, but it seemed it had been drops of blood.
Tae-un rubbed his cheek against the cheek of the man who could barely speak and was only panting.
“Did you like it when I did it cutely?”
“Nng…”
Kim Si-baek managed to raise his hand and stroke Tae-un’s forehead, smoothing his disheveled hair.
“If you’re cute one more time, I’m going to die of the ‘death from over-pleasure’ first…”
Despite having just engaged in sex that violently hammered pleasure into him, Tae-un smiled clearly like a boy and pressed his lips against Kim Si-baek’s. Savoring the sweet touch sliding softly into his mouth, Kim Si-baek was able to momentarily forget the things that scattered his mind, like the system.
✽ ✽ ✽
It was around the time Tae-un entered middle school. The boy, who had made a flashy debut in middle school through a brawl with delinquents, asked one day in a very serious tone.
〈Why hasn’t my voice changed yet?〉
Kim Si-baek found it a bit unexpected. Since Tae-un had started saying it was embarrassing and refused to go to the public bath together, he thought puberty had hit, but it seemed the physical development and growth hadn’t caught up with his heart yet.
Thinking of the other children around them, Kim Si-baek thought, ‘Well, I guess…’
Pi Min-hyeong was running around laughing “Khahaha” with a husky voice that sounded like grinding gravel due to his voice change, and Seo Gae-un had grown rapidly like a bean sprout, already surpassing 170 centimeters. Since he was the only one whose secondary sex characteristics hadn’t started, it was natural for him to be anxious.
〈It can be late depending on the person, so don’t worry. Do you want to grow up quickly?〉
〈I want to become an adult like Hyung soon.〉
〈That’s a problem. Once Un-i becomes an adult, no one will want to kiss Hyung.〉
Recalling the kissing incident from when he was drunk, Kim Si-baek put on a mock-melancholy expression. His heart already ached imagining a fully grown Tae-un refusing a kiss, saying, “I’m not a child anymore,” like other kids.
At the playful complaining, Tae-un’s expression softened and he gave a beaming smile.
〈Because even when I’m all grown up, I’ll always be Si-baek Hyung’s cute Un-i. Next time, I’ll be the one to kiss Hyung.〉
The proposition that the adult Tae-un is still a cute and lovely child is an eternal truth that would not change even if the earth split in half. However…
‘But a certain part grew in a way that isn’t cute at all…’
As he unconsciously countered the old memory encountered in his dream and snapped his eyes open, someone planted a loud, smacking kiss on his cheek.