To say that Gio was used to pain…
In a way, it was true. His mental tolerance for pain was certainly much higher than a normal person or even a seasoned Sequencer. Even if he was in pain, he could push through it and endure unless it truly became impossible.
However, his body didn't regress with his soul. His body's pain tolerance, the source of the signals his receptors sent to his brain, was still untrained and had only been toughened for a period of three months.
As such, even if he could endure it for longer periods, the level of pain he could endure was still low.
What he felt when he fought against the serum was pain that almost exceeded the limits of his physical tolerance. He could physically feel his nervous system burning up as his nerves were overloaded with stimuli.
His skin glowed a bright reddish-orange color, illuminating his veins and blood vessels within the hellscape.
However, he still pushed through it and focused on the formation of the core.
Gio was absolutely focused. The outside world completely disappeared from his perception, leaving him alone in the world of his body.
The Aether moved like a snake, slowly and methodically slithering along the most natural path it could find. It didn't know it was being guided, and it didn't know it was being corralled.
The Aether and blood from the serum remained where they needed to be, strengthening his body as it was meant to. The rest traveled that path until it arrived where he wanted it. The natural processes occurred, leaving him with nothing to do but bear it.
The world went dark. He focused with no purpose other than to focus, counting the seconds and feeling the changes within himself.
His bones were fortified first, followed by his muscles. He felt his body becoming noticeably heavier as mass was built where it didn't exist before.
The blood flowing through his body pumped faster and smoother, and he felt like every jolt in his fingers registered in his mind at lightning speed.
In reality, the changes weren't nearly so drastic. Gio's body was certainly enhanced, giving him a stronger foundation than the average newbie Sequencer. He was stronger and faster to the point where he could probably have a fistfight against an adult without losing his ground, but that was the extent of it. He wasn't miraculously granted herculean strength.
Merely, when his original state was that of an untrained teenager, every change felt dramatic.
The time passed slowly. The Old Lady remained in the test chamber alongside him to monitor his condition, but she didn't see any abnormal effects.
Other than the original spike in the metrics, his readings were almost completely uniform throughout the entire process.
'The process is normally meant to take from six hours to a day...is his body more receptive to the serum than most?'
In only a short three hours, the volatile energy field around him calmed down. His expression eased, and his skin stopped glowing like hot metal.
Another minute later, he opened his eyes.
"Huu…"
He took a deep breath. His lungs no longer stung with every movement, so he truly enjoyed it.
Putting his hand to his chest, he felt his powerfully beating heart.
And, of course, he felt the slight warmth of the new entity existing below it.
There, in a cavity between his lungs, there was now a purple-black orb that freely floated in place, constantly revolving yet never tipping off its axis.
That ball seemed to do nothing and have no effect at all. It existed merely to exist.
'That's true for now. At the moment, the Aether Core has no use. It's only an accessory that slightly lends to my bodily strength.'
However, the moment he actually gained power, the Aether Core would become more important than most other things.
'It's an unexpected gain, but an amazing one nonetheless.'
He smiled and gripped his fists.
'I feel like my body reacts to my thoughts faster now. There's also a considerable difference in the feel of my grip.'
His strength had definitely increased, and alongside it, his defense and endurance as well.
His stamina…
'It has probably dropped for now, but once I'm used to the changes, my upper limit will be higher.'
"How do you feel?"
Once again, it was the Old Lady who broke him out of his thoughts.
With a smile still on his face, he responded.
"I feel great."
It wasn't a lie at all. Once the pain passed, he felt like he'd entered nirvana. He breathed clearer, saw better, heard better…
He didn't care if this state would mean nothing once his Bloodline Sequence had evolved a couple of times. It was still something to be proud of.
He looked over at the Old Lady, his thoughts muddled.
'She was always like this.'
She clearly had this ready for him already. Was there anyone else she could be thinking of using it on?
She always treated him like her own son, and even back then, it made him feel strange.
Why was she so kind to him? For what reason did she give him such consideration? Was she planning to make him pay her back for her help, or was she really just so magnanimous?
She never told him in the past. If he ever brought up the issue, she'd respond simply with a, "You think you're special? I just know how to treat my people well."
Gio knew it was more than that.
'This time, I'll have to get to the bottom of it.'
He couldn't accept all of these favors if he didn't at least know why he was receiving them.
'But for now, I have no choice but to thank her and accept it.'
There wasn't anything he could do to repay her kindness right now. In the future, however, he would make sure to pay it back by any means.
'And that's a matter completely unrelated to saving her and Gastle from their demise.'
Gio shook his head and cleared it.
"...we don't know about any potential side effects, so be sure to visit me if you feel anything odd."
The Old Lady had just finished a monologue, so his timing couldn't have been better.
She looked at him for a moment before heaving a sigh.
"You didn't hear a single thing I said, did you?"
His smile twitched for only a moment before he caught it.
"What do you mean? I heard all of the important parts."
The Old Lady rolled her eyes. She knew him better than to believe him.
"This kid… Haa, if you're so excited, then just go. Get your things from Seb and use the main lab for whatever you need. When you've decided when to leave, let me know and I'll send him to accompany you. Alright?"
She looked exasperated, but he could tell she was just giving him an excuse to leave.
"Alright," he said.
"I won't forget to let you know. And, don't worry. I know how to be careful now."
Speaking such words of affirmation, Gio unbound himself and jumped off of the chair.
Since he had her permission to continue, there was no need to wait any longer.
He could proceed with the beast-hunting plan far, far earlier than he ever expected to.