Chapter 378 (Se-young)
Translator: RaidenTL
Chapter 378 (Se-young)

(Future Se-young)
Inhaling the crisp air, Si-woo strode across the grass yard toward the front gate of Aunt Seon-ju’s house.
As he headed for the exit, he scanned the perimeter of the yard, a satisfied smile playing on his lips. The inexplicable sense of unfamiliarity he had felt when he first brought Se-young here this morning was gone.
Beneath his clothes, Si-woo’s massive penis remained rock-hard.
He no longer felt the need to hide his arousal or his erection in front of Se-young—or any of the other family members, for that matter. At any moment, he could now force his engorged cock into the wet fissures of the women who had become his slaves.
An overwhelming sense of conquest and euphoria surged through him, making his head spin with delight.
Ben, who had been lying dejectedly in a corner of the yard, now turned his head toward the wall, pointedly avoiding Si-woo’s gaze.
The entire space felt comfortable, as if everything within it was under his absolute control.
From behind, he heard the footsteps of his younger sister, Se-young, following him across the grass. Si-woo glanced back at her as she approached with a hesitant, awkward gait.
Se-young was still wearing the light blue denim dress and orange socks she’d put on that morning. The only thing that had changed since they left home was the orange dog collar around her neck.
Like a piece of jewelry serving as evidence of her transformed relationship with her brother, the orange dog collar sat firmly around her throat. The leash attached to it was tucked inside her dress, wedged between her breasts. The handle of the leash peeked out from under her skirt, dangling against her thigh like a broken pendulum.
Se-young seemed to be trying her best to look at Si-woo with her usual bright smile. However, her face was gradually contorting into an awkward grimace, as if she were in significant distress. She couldn't stand still, her legs twisting and pressing together at the thighs.
It seemed Se-young was having a very difficult time keeping up with Si-woo’s pace because her bladder was about to burst.
"Se-young, do you think you can hold it until we get home? I’m planning on taking the long way around through the park..."
Si-woo spoke playfully, looking back at her while thrusting his erect cock forward against his clothes.
Startled by his suggestion to take the long way, Se-young shook her head vigorously before she could even find the words to speak.
"I-I don't think I can hold it that long, Oppa! Even now... Heeing~ Can't I just go back inside for a second, pee, and come right back out?"
Se-young pleaded with a desperate expression.
Until now, she had always maintained an air of relaxed superiority, subtly mocking and teasing Si-woo. This was the first time she was truly begging him, her voice filled with sincere entreaty.
It wasn't an act for their roleplay; she was genuinely flustered.
—Though even this might be part of her brilliant acting—
Regardless, the sight gave Si-woo a thrill so intense it made the hair on his neck stand up.
"No."
Si-woo flatly rejected her request.
The smile Se-young had been struggling to maintain vanished from her face.
In that moment, a surge of sadistic excitement washed over him. Blood rushed violently into Si-woo’s already swollen penis, making it throb with power. The muscle aches and fatigue he had felt moments ago vanished instantly, replaced by a fierce urge to pin Se-young down right there in Aunt Seon-ju’s yard and ravage her.
Yet, even as he felt that dark desire, seeing the light fade from his sister’s face made a part of his heart swell with a touch of pity and compassion.
"The house is too far, so I'll let you go once we get to the park."
Si-woo spoke soothingly, as if comforting the increasingly miserable Se-young.
Se-young pressed both hands against her groin and twisted her legs, glancing longingly back and forth between Si-woo and Aunt Seon-ju’s front door several times.
"Okay... I understand."
She hesitated, but seeing Si-woo’s firm expression, she realized she had no choice. She nodded, forcing a smile back onto her face.
Si-woo slowly led Se-young across the grass yard toward the gate leading outside.
* * *
Clack!
Si-woo opened the iron gate of Aunt Seon-ju’s house and stepped out into the residential alleyway. It was a fairly wide asphalt road lined with houses.
Stepping outside the gate, Si-woo felt a strange, lingering sense of awkwardness.
Thud!
After he had walked a few paces, a loud noise erupted behind him. It sounded like the roar of a distorted, twisted space suddenly collapsing and closing shut.
Si-woo flinched, his shoulders hunching at the sound. It was surely just the sound of Se-young closing the iron gate as usual, but...
Along with the metallic ring of the gate echoing like an afterimage, he heard Se-young’s small footsteps behind him. Si-woo turned around to confirm the gate was closed.
When he turned, Se-young stopped in her tracks and looked at him with an awkward smile.
"Come walk beside me."
Si-woo called her over to his side. Se-young approached him with a hesitant posture.
As she stood beside him, Si-woo stole glances at the soft flesh rising beneath her collarbones and the skin exposed under her armpits. Even by the standards of a Beginner Academy student, Se-young’s outfit—worn with nothing underneath—looked incredibly provocative.
Si-woo’s gaze swept over her smooth back, her slender waist, her ripening hips, and her plump thighs before returning to her neck and collarbone.
The orange leash extending from her neck was wedged deep into the cleavage between her breasts. The leash, about the thickness of a thumb, disappeared between her mounds.
Had Se-young’s breasts, which he had thought were just small since she’d only recently started developing, grown that much already?
Si-woo felt a fresh wave of admiration.
He reached out and touched the leash where it pressed against the top of her cleavage. Se-young flinched and pulled her shoulders back in surprise, but she quickly relaxed and pushed her chest forward.
Even though she was now flesh he could touch whenever he pleased, Si-woo found himself feeling strangely cautious when it came to Se-young.
"Is it uncomfortable?" Si-woo asked gently, tugging on the leash wedged in her cleavage.
"Ugh... mm~ It chafes a bit down there, but I think I’ll be okay for a little while. Hehe~" Se-young replied with an awkward smile.
"How’s your neck?"
Si-woo asked, sliding his hand from her collarbone up toward her throat. He felt her breathing quicken slightly.
"Yeah, the inside is well-padded, so it doesn't hurt as much as I thought it would," Se-young answered, her face flushing.
Si-woo moved his hand to the back of her neck and stroked downward. His hand brushed against the tender skin of her exposed shoulders and upper back.
Though he had touched Se-young’s body many times before, he stroked her now as if it were the very first time.
Eventually, his hand reached the boundary where her bare skin met the fabric of her dress. He slipped his fingers inside.
As he slid his hand under the denim dress and felt the skin of her back, the sensation of her smooth, delicate flesh rubbed against his palm. He felt a precarious sense of liberation, as if he were freely entering and exiting a forbidden territory.
Caressing Se-young’s back in the middle of a residential street, Si-woo savored that feeling of freedom.
After stroking her bare back a few more times, he pulled his hand out. This time, he moved his hand down her spine to her waist, where the curve of her buttocks began.
He cupped his palm slightly and placed it on her pelvis, just above her rear. Se-young’s buttocks tensed up as if she were startled.
Si-woo slid his hand down further, covering one entire cheek with his palm, and gave it a firm squeeze. The moderately plump flesh of her bottom was crushed into his palm.
He had squeezed her buttocks this morning on the way to Aunt Seon-ju’s, but the sensation now felt quite different.
Se-young’s body, which had been stiff with tension, began to tremble slightly.
With his hand still firmly gripping her rear, Si-woo glanced down between her thighs.
A clear, transparent fluid was trickling down the inside of Se-young’s legs.