Chris looked at the empty Deer Anthro vial, and noted the “causes size increase” side effect. It dawned on him that he probably should have read that more carefully before he poured it in his coffee.
“Why would a deer potion cause a size increase?” He whispered to himself. He quickly remembered that he had much, much more pressing issues to deal with, like the fact that his mom had drank his coffee, and the potion mixed into it, by mistake, and if the note on the box of vials had any sort of truth to it, it was gonna make his Saturday WAY more interesting than he’d prefer.
He put the brakes on his train of thought. What was he worrying about? This WAS all making the big assumption that the note on the box was telling the truth, after all, and he hadn’t proven anything yet. It was most likely just a silly prank, he told himself, mentally downplaying his own earlier curiosity.
He smiled, shook his head, put the lid back on the empty Deer Anthro vial, went back to his room, and placed it back on the folding rack he had pulled it from.
Then he saw it refill with the same dark green liquid, with no apparent source, despite being sealed tight.
His eyes nearly bulged out of their sockets as he realized two things:
1. Magic, (or sufficiently advanced technology,) was real. And
2. It would soon give him some very big problems to deal with.
His hands scrambled over the box, digging into every crevice, hitting every button, trying to find any other notes with extra details. How long would the change take? How could he reverse it? Could the change be stopped? The box had drawer after drawer, hidden compartment after hidden compartment, to the point that he was pretty sure there was more space for these vials inside the box than should have been physically possible, and potions for normal and anthro variants of just about every species on Earth, (and maybe a few not of this world,) but not a drop of information to be found.
“There’s gotta be SOME way to fix this!” He groaned. He was just about ready to give up, when his hand grasped a human vial.
Of course, he thought to himself. He hadn’t heard any sign of transformation so far, so maybe if he could slip this into another drink of hers, it could cancel the effects before-
“WHAT ON GOD’S GREEN EARTH IS THIS?” Came a scream from the living room.
Well, beating the potion to the punch was out of the question, then. But fixing it was not. In fact, if he played his cards right, he could end up reversing it without anyone being the wiser.
He grabbed the vial and rushed back to his living room, where his mother was already sporting a cervine snout ending in a black nose, with patches of light brown fur atop it, and more growing in clumps over her face.
“Mom!” Chris shouted, trying his best to sound oblivious. “What happened?”
Chris’s sister, Tanya, rushed down the hall seconds later. “What’s everyone- AAAH! MOM WHAT TH-”
Their mother interrupted with a yelp as her ears seemed to get tugged on by an invisible force, growing longer and fanning out to each side at a roughly forty-five degree angle, short fur covering the back of each ear completely. White fur grew in patches under her chin, spreading down the front of her neck and chest, while the light brown fur coated the rest of her face completely.
She started panting, and forced herself to take deep breaths before speaking again. “I… I don’t know… how this happened… I had just… finished my coffee a minute ago…” She stiffened, and took a few more deep breaths.
Chris blinked, and looked more closely. It seemed like every breath she took was making her just a little bit bigger. And not just taller, either. As more of her arms and legs were exposed by her outgrowing her robe, he could see muscles bulging underneath her skin.
At age sixteen, Chris had outgrown his mother, reaching about five feet, nine niches, but already, she’d dramatically overtaken him at least seven feet, and still growing.
“...And then…” she continued, still panting, “then this… started happening…”
She huffed, and began to pull at her robes, brown fur with white speckles now clearly growing over every visible part of her body. Her feet seemed to clench up, her toes turning dark and hardening, two toes on each foot growing into cloven hooves, the others migrating back on her narrowing and elongating feet, becoming little dewclaws, instead. Her fingers, meanwhile, grew thicker, the outermost joint of each digit becoming the same material as her hooves.
She gasped, and began undoing her bathrobe. “C-can’t br-breathe!” She motioned for her children to get out of the room as she began to remove her clothes before they either got ripped, or constricted her.
Chris and Tanya both rushed back into the hall out of sight of their mother.
“What WAS that?” Tanya shouted. “Why would mom just suddenly start turning into a freakin’ GIANT DEER?”
Chris glanced back down at the human vial in his hand, “No clue! Ugh, why’d she send us out? I’d like to get to the kitchen and get her some water!” No getting to the kitchen without going through the living room. He briefly remembered the bathroom, before also remembering that dropping the potion in clear water would probably discolor it and make his mother hesitant to drink it. No, better to hide it in juice or something.
There came a bumping sound, and a low groaning from the living room. Despite both his mother’s orders, and his hesitancy to look, Chris peeked around the corner, where he saw his mother’s new form, sitting on the floor and holding her head, turned away from him, luckily.
She’d managed to get the robe off, leaving her body bare, (though the speckled fur covering made it a little less awkward-feeling for Chris), and letting him see the short fuzzy tail on her backside. Even from the back, her magically-enhanced fitness was clear. Her continued growth had brought her to around double her original height, now nearly eleven feet of amazonian deer lady, stuck in just under eight feet of vertical apartment clearance.
Chris considered his options.