Regression Guidelines For the Supporting Character

Moonlight streaming in through the window cast its glow over Cha Sahyeon’s neck. Cha Seohu, quietly gazing at that unusually pale skin, pulled an item from his inventory.
A green jewel on a black ribbon sparkled in his palm.

It was within arm’s reach. It would be easy to lean in and wrap the item around Cha Sahyeon, who was sitting close with his body bent forward.
And yet, Cha Seohu didn’t move so easily. His eyes narrowed as he looked down at the choker.
‘…This is the right choice.’

No matter how much fate had changed, no matter how different the future had become, the Seed of Catastrophe was still inside Cha Sahyeon. There was no way he could allow someone that dangerous to wander around freely.
‘It’s my responsibility.’
He had made that decision the day he regressed—when he saved Cha Sahyeon and fled the lab. He’d sworn to carry the burden of the Catastrophe alone. He didn’t want to drag others into it—not the members of the Circle Guild, not anyone else.

Sharing a bed with the young Cha Sahyeon, seeing Ryu Sunghyun look at him like a stranger, living in a future that was diverging from the one he remembered—none of it had shaken his resolve. It had only strengthened it.
“……”
He wasn’t regretting that decision now.

The reason Cha Seohu was hesitating… was because of what truly frightened him.
[A gift… For me?]
That trembling voice, those flushed cheeks, came rushing back to him.

[You bought it… for me?]
That shy smile as he hugged the paper bag with the game console inside.
[I like this. It’s the first one you made.]
[I got scared. When I saw the Rift open near where you were, I was so scared…]
[I was mad, but… you looked really hurt, so I just…]

Like pages flipping, every moment he’d spent with Cha Sahyeon flashed through his mind.
When he insisted on eating the food Seohu made.
When he suddenly showed up uninvited.
When he woke up in the hospital.
When they looked up at the night sky together as fireworks exploded.
[You’ll be much safer there. I understand.]

Even the conversation they had right before the kidnapping—every memory he had with Cha Sahyeon felt too vivid.
That was the problem.
Cha Seohu had genuinely cared for young Cha Sahyeon as his guardian. He wasn’t an idiot—he knew there had been affection in that care.
And that was what he feared.

He feared he would come to feel the same affection toward the current Cha Sahyeon—the one who still carried the memories of the Catastrophe. That one day, if the time came when he had to kill him, he would hesitate.
Cha Seohu bit his lip, tightening his grip. The choker in his hand crumpled slightly in his clenched fist.
But only for a moment. Then, his fist slowly opened.

He’d been thinking about this ever since they reunited and he received the item—but the conclusion had never changed. He had to give it to Cha Sahyeon.
Saying there was no time to hesitate was just an excuse. There was only one road ahead, and it didn’t matter when he started walking it.
“Lower your head.”

Cha Sahyeon lowered his head slightly. Through the tousled strands of hair, his green eyes sparkled with nothing but joy.
That childish face looked exactly like the one that had smiled after receiving the game console, and it made Cha Seohu’s heart sink bitterly.
Click.

The soft velvet of the choker wrapped snugly around Cha Sahyeon’s neck. The green jewel at its center gleamed the same shade as °• N 𝑜 v 𝑒 l i g h t •° the green sapphire earring he wore.
‘So that settles the L-grade aura… at least for now.’
Cha Seohu felt a bit of relief, despite the storm inside him. The L-grade energy that had always unnerved him seemed to have settled.

Just as he was about to check the status window to confirm—
Crackle!
“……!”

Sudden sparks erupted and engulfed Cha Sahyeon’s body. Startled, Seohu tried to reach out, but was instead overwhelmed by a surge of power that hit like a crashing wave.
“Ugh…!”
A sharp, stinging pain like being pricked by needles spread through his entire body. He gritted his teeth and endured it, and soon the storm of energy subsided.

Even though it had only lasted a moment, his arms and legs tingled, and sweat soaked his back. Trembling, he looked down at his arms, then quickly lifted his head.
“Cha Sahyeon, what was that just now—”
He couldn’t finish the sentence. His eyes widened.

“Cha Sahyeon?”
That dazed name slipped from his lips as a small, pitch-black head poked up from beneath the robe’s folds.
“What the…”

Cha Seohu reflexively took a step back, stunned.
A chubby-cheeked face. Wide, round eyes. A tiny frame that barely reached Seohu’s waist. The oversized black robe began to shrink and adjust around the small body.
The clothes beneath the robe weren’t shadows either—they slid off entirely. Wrapped tightly in just the robe, Cha Sahyeon looked up at him and said,

“It’s the item’s effect.”
“…What?”
Even his voice had turned childlike.

“My body is connected to my aura. When the aura is suppressed, my body shrinks.”
“…You mean, the item suppressed your energy, and your body got younger to match it?”
“Yeah.”

As soon as he answered, the status window popped up as if it had been waiting.
User Information: Sahyeon (Villain)
Age: 22
Main Skill: Living Shadow (A-rank)
Title: The Master of Shadows
Attack Power: A-rank
Attack Speed: A-rank
Movement Speed: A-rank
Agility: A-rank
Special Notes▼
└ Seed of Catastrophe (62% Progress) (Synchronization 60% Progress)

The sections previously marked as L-grade had all shifted to A-rank.
“So it wasn’t just an item to hide your aura?”
“Technically, it suppresses it. My aura was too strong to just hide.”

Well, of course—it wasn’t just S-rank, it had surpassed even SS-rank and reached L-grade.
Cha Seohu took a breath and studied Cha Sahyeon again.
Now that he looked closely, he did seem a bit taller than before, and his face looked slightly less round. Maybe it was because his stats had risen from B-rank to A-rank.

‘Looks like he grew around five centimeters.’
As Seohu pondered this, Sahyeon stepped forward—then immediately stumbled.
“Ugh!”

Thud!
He tripped over the loose robe and fell flat on the floor. Seohu stared down at him with an incredulous expression.
“What are you doing?”

“…It takes a while to adjust.”
Sahyeon mumbled like he was making an excuse. Was it Seohu’s imagination, or were his pale cheeks slightly flushed?
Outwardly, he looked like a kid, but internally he was a fully aware adult and an awakened being. Seohu thought he’d adapt quickly—but apparently not.

“Haa…”
With a deep sigh, Seohu watched as Sahyeon planted his small hands on the floor and got back up.
Then, with perfect timing, the door flew open, and Ryu Sunghyun, Song Jiwoon, and Wang entered in succession.

“Hunter Cha Seohu, we felt a powerful aura from this room—!”
“Uh…”
“Hm?”

Ryu, who had shouted with concern, froze first. Song Jiwoon and Wang, who followed behind, also looked confused.
All three sets of eyes locked on the young Cha Sahyeon clinging to Seohu’s chest.
‘…Great.’

They must’ve sensed the energy spike caused by the item and come running.
When Ryu Sunghyun met Sahyeon’s gaze, his expression bordered on horror. Understandable—after all, the boy had turned into an adult, and now back into a child again.
“This is, uh…”

Just as Seohu was trying to figure out what to say, Wang spoke up first.
“Cha Seohu. Is that child the one you brought?”
“If you put it that way, yes.”

Wang looked back and forth between Seohu and Sahyeon with a peculiar expression, then blinked and asked again.
“…Did you give birth to him?”
“…What?”

Seohu went completely blank. Ryu Sunghyun and Song Jiwoon both turned to Wang with unreadable faces.
Silence fell over the room.
“…I’m a man.”

The absurdity of the question had been so far beyond imagination that Seohu could only mumble back in bewilderment. Only then did Wang clear his throat awkwardly, seeming to realize his mistake.
“Ahem. My apologies. It’s just… the child resembles you so much, and in my world, birth isn’t limited by gender, so I got confused…”
What the hell kind of conversation is this?

He was starting to feel like he was losing his mind. Seohu pressed his stinging eyes with a weary hand.
“You came because you sensed the aura burst, right? Don’t worry—everything’s fine. This child is… my younger brother. The big, black-robed one who was following me around earlier.”
There was no excuse to give. He couldn’t fool all three of them, so the only choice was to be honest. Well, mostly honest—with a few lies mixed in.

As he felt Sahyeon’s warmth clinging to him, Seohu looked at the others and gestured.
“Come in. This is going to take a while to explain.”