"So you wanted me to help with science?" C asked, shaking off the last traces of nausea from the shortcut Sans had pulled her through. She was in the Lab, Gaster's private one under the new house that is. The Royal Scientist himself was hunched over his desk and didn't look up to reply,
"That's a broad term to use." He deadpanned, C snorted,
"Its the term you used."
"I did not!" Gaster argued indignantly, "And even if I did, it would've been because you're too dumb understand the proper terms."
Sans chuckled, startling C as she'd forgotten he was still there.
"just tell her dad." he said, wandering around the room and looking at whatever caught his eye. As Gaster was still getting set up, there wasn't much, but it was worth a look anyway. One could never be bored in the Lab of a science-crazed skeleton. Finally finished with whatever notes he appeared to be writing, Gaster stood up straight, his spine cracking with the sudden movement.
"I want to research your Soul." He said simply, shifting through some of the papers he held in his hands. C raised an eyebrow and pulled her Soul out into her palm,
"This? I mean I guess you can, but why?"
Gaster came over to C and, with a quick glance to ask for permission, he scooped her Soul into his own hands, where it floated above the holes. C felt a shiver of fear go down her back but she ignored it, her Soul wasn't going to shatter with Gaster just holding it. She doubted anyone would be very happy with Gaster if he did end up killing her, whether she was important or not.
"I wanted-" Gaster began, ushering C over to his work table so she wouldn't be so far from her Soul, "-To test how different your Soul is from the other seven traits."
Sans stopped his aimlessly searching of the Lab and joined in, grabbing a sheet of paper from one of the many scattered piles and showed it to C,
"so each soul is defined by a trait right? but they all have a trace amount of every other trait too, that's why humans are all determined, but not the point of timeline resets like frisk is." Sans explained, indicating to the measures of coloured strips on the page. C nodded,
"Did you want a colour stripe of mine then?" She asked, Gaster grinned,
"If it wouldn't be a bother."
C shrugged and flopped down onto a nearby desk chair, flipping her head over the back to stare at Sans upside down.
"Howdy Sans." she giggled, her fingers twitching in a natural reflex to her Soul getting jabbed with needles and the like. She sucked in a breath suddenly as a shot of pain went through her chest, making Gaster look up from where he'd just stuck some sort of instrument directly into the black heart.
"Sorry C." he apologized, removing the device. C grinned weakly at Sans, who rolled the lights in his sockets.
"so uh. how's it going?" Sans asked, scooting his chair closer to C so he could poke her repeatedly in an irritating manner until C slapped his hand away.
"Almost there Sans. The results do look interesting so far." Gaster replied, watching the two poke and slap each other in the most casual way possible. A small beep sounded to alert Gaster as he turned back to his work table. A piece of paper was in the process of printing, showing the results of C's Soul traits. Gaster picked it up once the paper was fully printed and frowned.
"Now this is unusual."
C sat upright in her chair and took the paper to determine it for herself. It showed something like a chromatogram of colours, just with an excess of black at both ends. The black also spread it's way through the other colours, winding into interesting patterns. C nodded appreciatively.
"Looks cool. What does it mean?"
"Well." Gaster began, preparing his explanation, "Each Soul trait is a colour and as far as normal goes, you have an average amount of each trait in your Soul. There's a lot less Determination however, almost reaching the average monster's level. My hypothesis is that with your black Creativity mixing as it does with all the other traits, it takes over Determination as your strengthening trait. So, whilst all other humans I've seen survive with Determination, whatever trait they have and traces of all the others; you survive much like a monster, with something other than Determination."
C blinked in confusion, her mouth slightly open as she tried to process the information.
"basically you have creativity instead of determination." Sans said, putting it simply for the confused human. Apparently Gaster had no concept of non-experts and expected everyone to be on the same level of understanding as he was. C nodded, understanding now. A strange look suddenly came over her as she continued to think and she quickly reverted her gaze back to the paper in her grip.
"what's the matter, something wrong?" Sans asked, his sockets flickering to black.
"N-no. You can't see any other information about my Soul can you?" C asked, sounding ever so slightly nervous. Gaster frowned, turning back to his desk so Sans could handle her question as he bent over a stack of books. The short skeleton himself glared at C suspiciously for a second but he quickly covered it up with a lazy grin when she looked up from the paper.
"not if we just did a trait test. why you'd ask?"
"Just wondered." C shrugged, "Was there anything else you wanted to experiment?"
Gaster thought for a minute,
"I would like to see if your lack of Determination affected your physical self, but I have no idea how I'd test that on a human." he replied, "In the meantime, you can continue with your schooling."
Taking up the paper from C and slotting it into a battered folder labelled 'Soul Research', Gaster proceeded to then ignore the human girl. Sans yawned, the space around him warping as he vanished upstairs. C blinked sleepily a few times, pulled her legs up and dropped her head down to her chest. Her Soul floated over from where Gaster had let it go and went back into her body. C herself fell began to nod off and fell asleep, lulled by the quiet hum of machinery and Gaster's mutterings.
===
Gaster kept working throughout the evening, almost completely uninterrupted save one angry text from Toriel that he swiftly ignored. He was far too occupied reading through those books, wishing for nothing more than for his suspicions to be put at ease. Something about the way C had seemed so nervous about the other results on her Soul made him uneasy. She was obviously hiding something, but what? Truth be told, Gaster really had started to like C, but that would do nothing to save her from his wrath if he found the slightest thing wrong with her.
That in mind, the Royal Scientist began to read over some very old books and scriptures that had some of the earliest recorded experiments on human Souls. He'd only recently salvaged them from the old Underground Lab, but hadn't had the time he'd wanted to properly read through them. The books were tattered, with entire paragraphs occasionally unreadable and sometimes large sections of pages missing. The information Gaster could glean from the remaining, legible pages was rather interesting, and had it not been for a soft knock at his door, Gaster could have stayed there all night. As it was, he set down the books and let his visitor enter.
"Hey Doctor Gaster." Frisk said, casting their gaze over to C and furrowing their brow, "Could I ask you something?"
"I guess, what is it?" Gaster sighed, clearing away his books and bringing up a chair for Frisk to sit. The young child was the only other human who Gaster would tolerate in his Lab, and that was purely because everyone else loved them. He had no evidence of Frisk having been the one to break the barrier, but it was more unlikely that the entirety of monster kind would lie for the sake of one measly human child.
"Do you know who Flowey is?" Frisk asked softly, breaking Gaster out of his thoughts. He smiled coldly at them, recalling the very familiar yellow flower he'd met as just a shadow.
"If you are referring to the dead prince, then yes. I know Flowey."
Frisk let out a sigh of relief, settling more into their chair. This was going to be okay, they could get the help they wanted. Gaster leaned forward, knitting his phalanges together and resting his chin on them.
"I was wondering if it were at all possible to make him a new Soul." Frisk started brightly, "I've seen what taking other Souls can do, but if we were to give him one of his own..." they trailed off, not sure how to continue. Thankfully, Gaster seemed to understand. He sat up straighter, mulling over the result of Frisk's proposal.
"I think..." he hummed, running through the possibilities in his mind, "With the correct method, that is entirely possible. We would be constructing an artificial Soul from scratch of course, and whilst I have done that twice before, bear in mind that it's harder than you may believe it to be."
Frisk frowned, confused at what Gaster meant.
"You've done it before?" they repeated. Gaster beamed,
"Yes of course! How else do you think Sans and Papyrus came about? I was the only skeleton left after the War you know." he explained, with a mixed expression of melancholy and happy. Frisk's eyes widened as they realised the missing piece they'd been looking for so long ago. The book Toriel gave them was wrong, a skeleton had survived the war. Gaster survived the war and then made Sans and Papyrus. How fascinating that the book got it wrong. But back to the matter at hand, they'd ask him more questions later.
"So you could replicate that?" they asked. Gaster nodded.
"I'm certain I have a way to create a Soul. Although to do so, I shall need some help. Would you mind waking C? She has work to do."