Regression Guidelines For the Supporting Character

A crushing pressure weighed down on my chest, making it hard to breathe. I shifted my body, trying to shake it off, but I couldn’t move at all, like I was bound by something.

"Ugh…"
A pained groan escaped my lips. After struggling for a while, I finally opened my eyes.
The bedroom was dim, with the curtains drawn. I blinked blankly and raised my hand to feel what was pressing down on my chest.

"Cha Sahyeon."
"Mmh."
Soft hair brushed against my fingertips.

When I called his name in my hoarse morning voice, he immediately responded and rubbed his cheek into my chest.
‘Unbelievable.’
A sigh of disbelief slipped out at his shameless behavior.

I’d definitely seen him lie down in the next room last night. I had no idea when he crawled into my bed again. It happened every day, yet I still couldn’t get used to waking up to it.
"At this point, don’t you think it’s time to give up and just sleep in your own room?"
"Then why don’t you give up trying to sleep without me…?"

Still clutching tightly to my chest, Sahyeon mumbled back with a sleepy tone that matched mine.
I brushed his messy hair out of his face.
"At your age, you should be sleeping alone."

"How old am I again…?"
"Uh…"
Yeah, how old is he?

He had recovered some of his memories, so he must be over twenty by now… but maybe he was over a hundred? Last time, he mentioned something about going through it hundreds of times. But then again, his memories weren’t perfectly intact, so counting them all as age might be a bit of a stretch.
While stroking Sahyeon’s hair, I got lost in pointless thoughts. I was seriously curious now—how old was he, really? But he didn’t know for sure either, so there was no way to find out.
‘Is he really over a hundred…?’
Meanwhile, Sahyeon had already fallen back asleep with his face buried in my chest.

If someone saw this scene and heard he was the Catastrophe, they’d never believe it. Of course, he might look sound asleep now, but the moment he sensed anything strange, he’d shoot up like a ghost.
Just then, the alarm on my phone blared from the nightstand. I lightly tugged on Sahyeon’s soft cheek as his eyelids fluttered open.
"Get up. Wash up and get ready."

Today was finally the day we were entering the Great Dungeon.
***
The Great Dungeon, larger than standard dungeons, took significantly more time to clear. And since it was an S-rank dungeon, a lot of prep was required for safety.

Spare clothes, food, emergency meds, knives, signal flares—everything you'd need in case of disaster had to be packed.
You never knew when you might get separated or lost in a crisis.
Thankfully, the inventory system made carrying supplies easy. While I was packing, Sahyeon returned from his room, having changed clothes.

"Hyung, is this okay?"
With the choker removed and his real appearance restored, Sahyeon looked at me, fully dressed.
A black T-shirt, leather jacket, and jeans. Clothes I’d picked out for today, and they looked good on him.

Especially the leather jacket—I originally bought it for my Cover disguise, but it was a bit big on me, so I had stored it away. It fit Sahyeon perfectly.
‘This should be inconspicuous enough.’
I’d considered getting him some defensive gear, but high-grade items were too expensive, and frankly, it didn’t seem necessary for Sahyeon. Regular clothes would do.

Since he was entering under a false identity, it was more important to blend in than to stand out.
"Come here."
Sahyeon, fiddling with the jacket in satisfaction, quickly came over at my gesture. I handed him something I’d prepared in advance.

It was the pearl Chronos had gifted me. If he took it, Sahyeon would appear as an A-rank even without the choker.
He swallowed the pearl with a slight grimace. At least he was obedient about things like this.
‘Not bad.’

The moment he swallowed it, the pressure of his aura reduced dramatically.
At this distance, the difference was striking. Hopefully the effect would last through the entire Great Dungeon raid.
"Anything hurting?"

"Nope."
Sahyeon shook his head quietly, looking far more cheerful than usual.
He always got excited when we went out with him in his real form. I guess being in the child form really was uncomfortable for him.

Right on cue, the doorbell rang. Kwon Taehyuk had arrived as promised to meet us before departure.
‘It’s better to explain now.’
He’d believe it better if he saw it for himself, and if I waited too long, the aura might be an issue.

Now was the only chance.
"Hunter Cha Seohu. Are you ready?"
Kwon Taehyuk entered the room with an innocent expression, but immediately stopped in his tracks when he saw the tall figure standing behind me.

"I’m ready. And this is…"
Taehyuk’s eyes darted as he stared at Sahyeon. He looked more shocked than I expected. What was that about?
"This is my younger brother. He’s been using an item to appear as a child. You’ve met him before, Guildmaster. Back then he was wearing a mask."

"Met him… before?"
"Yes. During the dungeon break. The guy standing next to Cover. I sent him to help you."
"Ah."

He must’ve remembered the guy in the dark robe and mask. Once recognition dawned on his face, I continued.
"My brother and I have been on the run since escaping the lab… so we ⊛ Nоvеlιght ⊛ (Read the full story) had no choice but to hide. It’s the same reason I’ve kept my skill rank hidden. Vice-Guildmaster Ryu and the Mountain Keeper found out while we were staying together in the snowy mountain. We weren’t hiding it from you specifically."
"I understand."

Kwon looked over Sahyeon’s real form with a subtle expression, then nodded as if he accepted it.
"I can see why you’d be cautious, especially after being captured by a lab that does human experimentation. That’s why I’ve been extra careful with guild security. I could sense that not just the district group, but also remnants of the lab were still pursuing you. You don’t need to feel any pressure over this."
"I really appreciate you thinking that way."

As expected of Kwon Taehyuk. The kindest and most well-mannered rich guy I know.
While I was feeling touched, he cleared his throat awkwardly and spoke again, more carefully this time.
"Ahem, so… the two of you…"

"Yes?"
"You’re still… brothers, right? Blood-related, I mean. That hasn’t changed?"
"Of course. Only his appearance changed."

Did he suspect something? I answered firmly and checked his reaction.
But contrary to my concerns, Kwon Taehyuk looked openly relieved and let out a deep breath. No sign of suspicion at all.
‘Why did he even ask that…?’

***
We rode the car Kwon Taehyuk had arranged and headed to Incheon.
After passing an entrance plastered with warning signs and tape, guarded by government-designated Hunters, we climbed for a while and reached the staging area.

The wide dirt clearing was packed with Hunters waiting to enter the Great Dungeon.
Just as Chronos had predicted, the total number of applicants was 552. From that, 100 were selected—including both me and Sahyeon under his fake identity.
As I stepped out of the car, I summoned the status window I had seen before.

《Sub-Quest: Protect Key Individuals in the Great Dungeon. (S-rank)》
[Sub-Quest: Protect Key Individuals in the Great Dungeon.]
Prevent the death of key individuals within the Great Dungeon.
Key Individuals: Sahyeon, Kwon Taehyuk, Ryu Sunghyun, Song Jiwoon, (Locked), (Locked), (Locked)

Warning! If even one of the designated 'key individuals' dies, the quest will be considered a failure.
‘Who are the other three?’
The entries marked as "Locked" made me uneasy. Would they only be revealed after entering the dungeon, like in the main quest?

As I entered the clearing, some familiar faces immediately approached.
"Hunter Cha Seohu!"
It was Ryu Sunghyun and Song Jiwoon, who had arrived earlier and were waiting.

I hadn’t seen Song Jiwoon since joining Yesung Guild, and he ran up with a puppy-like grin—only to freeze in place mid-step.
His eyes locked onto Sahyeon standing next to me.
Even though Sahyeon was wearing a hat pulled low and a mask to hide his face, Jiwoon probably recognized him instantly.

"Um, this person is…"
"My younger brother. We met at the mountain, remember? I brought him along for the Great Dungeon."
At my words, Ryu Sunghyun glanced over at Kwon Taehyuk, clearly checking whether I had revealed Sahyeon’s identity to him too.

Seeing Kwon quiet and composed, Ryu seemed to conclude things on his own and turned back to me.
"Will it really be alright? Once we enter the Great Dungeon, positions will be assigned, and you’ll likely be separated from your brother more often than not."