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Frisk shuddered to herself as she walked down the dark, dingy hallways of the True Lab, searching for more keys to activate the generator to get out of the creepy laboratory. She ran a hand along one of the walls as she walked, frowning as she noticed the thick layer of dust coating the tip of her finger. Either this place hadn’t been visited in a while, or… She didn’t want to think of the alternative. She steeled her resolve and continued to walk. She would never find her way out if she didn’t keep moving. One of the screens nearby flared to life, text covering the monitor. Curious, Frisk walked up and began to read.
“ ENTRY NUMBER 2
The barrier is locked by SOUL power..
Unfortunately, this power cannot be recreated artificially.
SOUL power can only be derived from what was once living.
So, to create more, we will have to use what we have now...
The SOULs of monsters.”
…the SOULs of monsters…? But how could Alphys use…?
Another monitor flickered to life further down the hallway. Frisk walked over and read it.
“ ENTRY NUMBER 5
I've done it.
Using the blueprints, I've extracted it from the human SOULs.
I believe this is what gives their SOULs the strength to persist after death.
The will to keep living... The resolve to change fate.
Let's call this power...
‘Determination.’ ”
Oh.
…She didn’t. She wouldn’t have.
A third screen powered on.
“ ENTRY NUMBER 13
one of the bodies opened its eyes.”
She did.
So… that was where those… things came from. They were… monsters who fell down, once. Injected with DETERMINATION to give their souls the power to hopefully break the barrier… but something clearly went wrong. She thought back to all the creatures she had seen so far. They resembled monsters she had met and befriended in her travels through the underground, but as if several of them had been mashed together. Was it that simple? Did the DETERMINATION somehow cause them to… meld together? Wait! She remembered something she read in Snowdinn’s Library about monster biology. “Monsters are made of magic”. Perhaps the magic of monster’s bodies couldn’t keep up with the strength of DETERMINATION? And they… melted? Frisk scrunched her lip. She wasn’t sure, but it was her best theory so far. But… how did that even help her right now? The information was horrifying… but what was even worse was that Frisk had no idea how to help them. She sighed to herself. She supposed that not everyone could be saved… no matter how much she wished otherwise. She clenched a fist. But that didn’t mean she wouldn’t try. She shook her head. She should keep pressing forward.
As she continued through the shadowed facility, she wondered how the strange fusion monsters feel. Were they… in pain? Did they feel confused? Did they have separate minds…? These disturbing thoughts plagued her as she continued to travel the shady corridors. She exited the cramped hallway she had been traversing and entered a surprisingly vast room, littered by beds. She wandered the room, shifting the beds’ covers to see if they contained anything useful. Nothing. She pouted. Aw man. A droning noise caught her attention. She turned towards the source of the sound, seeing a short hallway leading into another wide room. She walked over to the hallway, taking a peek into the other room. The noise was coming from one of the room’s walls, which was composed entirely of fans… for some reason. Suspended in the air were several white particulates. Frisk raised an eyebrow. She shrugged and looked down to the opposite end of the room, seeing a glint on the ground. Could that be one of the keys? She quickly hurried over it, the fans blasting her hair and clothes and making her very cold. Ew. But it was worth it, because she looked down to see the glint she had noticed earlier was, in fact, a key! Grinning, she quickly scooped it up. She noticed a switch on the wall next to her. Assuming it controlled the fans, she flipped the switch. No need to deal with that freezing artificial wind again.
The fans all shut off. The strange, floating white things suddenly started floating towards each other. As they made contact, they merged together, slowly forming a large ball of the same white substance. Uh, what? Why were they doing that? Wait… were the fans… Frisk facepalmed. Of course.
The gooey white sphere fell to the ground, with a very gross SPLAT sound. The white goo expanded out from the sphere, shifting into a body. Frisk took an involuntary step back as the creature continued to shift and warp. The thing was massive, easily standing at 7 feet tall, despite being a quadruped. It resembled a huge snow white dog, with a thick coat of fur covering its entire body. But it had one disturbing feature differentiating it from simply being a giant dog. Where its face should be instead existed a pitch black hole. An inky abyss that led to nothing. And Frisk was pretty sure she could see it dripping .
The dog amalgamation crept closer to Frisk, who instinctively backed away… only to hit the wall behind her. Fuck. The beast crept closer still. Frisk panicked, desperately looking all around for a way out of the situation. She did not want to fight that . Fuck, fuck, fuck, fuck!
She stood there, paralysed in terror as the creature loomed over her. And then she saw something she most certainly did not expect.
The canine had a thick, throbbing, fully erect, knotted red cock. Frisk was completely still in shock. Why…? Why was it… so… big… ? A faint blush coloured her cheeks. She shook her head, trying to clear those inane thoughts. Are you serious, Frisk? Not only is that thing beyond horrifying, it’s a literal dog for Christ’s sake!
But she couldn’t stop images from running through her head, causing her face to grow ever more crimson. Images of her and that dog’s big cock…
She felt a growing heat in her face… and between her legs.
She fell to her knees.
The large dog moved over Frisk, letting its girthy cock hang tantalisingly close to her plump lips. If she moved forward just an inch, she would come into contact with that thick weapon . Her breathing becomes heavy.
Determined… she has to stay determined.
She stared at the throbbing cock, her desire warring with her caution. Maybe… maybe just a little bit wouldn’t hurt, right?
She puckered her lips, leaning in, planting a soft kiss on the dog’s massive cock. The taste was indescribable .She tried to take a breath to calm her mind… and she deeply inhaled the dog’s potent musk, making her feel woozy and full of lust. She could feel her thoughts slowing down. She planted another kiss. And another. And another.
She couldn’t get enough.
Soon the dog’s cock was positively coated in Frisk’s saliva. It howled, as if making a command. Frisk stared for a moment, confused, but then it clicked. She raised her bare ass into the air, presenting it to the amalgamate. It wasted no time, quickly pressing its thick cock against her entrance and beginning to push into her.
She gasped in both pleasure and pain as the dog’s massive cock stretched her to her limits. “W-Wait- I don’t think it will f-fi-! Gah! Fuck !” She was cut off by a loud moan escaping her as the dog suddenly rammed its entire girthy member inside of her in a single thrust. She gritted her teeth as it began to move inside of her, quickly building up to full on thrusts. “Ah~, ah~, ah~...” Moans were the only thing that came out of Frisk’s mouth. “Fuck… harder ~”
Each of the dog’s thrusts sent waves of mind-numbing pleasure through Frisk’s body. The dog placed one of its paws atop Frisk’s head. It pushed down, pressing her head against the ground as it ravished her. Then it began to thrust even harder. Tears rolled down Frisk’s cheeks from the pure ecstasy she was experiencing due to the dog’s relentless pounding. Why… why was she here again…? “ Ahn ~!” The dog thrusted deep into her. To… find some secrets…? She n-needed to get- “Ah~, fuck~!” Another thrust deep inside her, rearranging her insides. No… that wasn’t right… “Oh, yes ~!” Frisk could feel her body memorising the dog’s shape. She wasn’t here for any reason except one: to be this Alpha’s breeding bitch.
Her eyes glimmered with her newfound purpose. She was filled with DETERMINATION. Her plump lips split into an air-headed grin and she altered her posture to allow the dog to more easily destroy her pussy. Her Alpha’s thrusts came even faster and harder than before. “Fuck me, Alpha~. Fuck this bitch and breed her~. Mark her as yours forever~ .” She moaned submissively as her insides were repeatedly pushed back to make room for her Alpha’s cock.
Thrust after thrust after thrust after thrust… they must have been there for hours, Frisk’s body and mind being ravished. And she loved every second of it.
She felt her Alpha’s cock throb. “You’re close, aren’t you~?” She inquired. “Do it. Cum inside me~. Give me your puppies ~.”
Her Alpha wasted no time in delivering what she desired. She gasped and moaned as she felt the flood of semen erupt from her Alpha’s cock, overflowing her womb with its superior seed. She was filled with monster cum. She could already feel the Alpha’s sperm impregnated her. A smile crossed her face.