Megamacropolis 3

 You wake up in a hospital bed far too large for you. The covers around you and divot in the sheets suggest that something much larger was lying in this space recently. A blanket like an entire field lies at your feet, mercifully not on top of you.   

 You think to yourself that you should probably find a better way of navigating this world than passing out all the time. 

 Though to be fair, it was a VERY large needle.   

 You sigh and rub your ass, finding the fur still intact. The wound where the equivalent of a greatsword went through is mercifully - though very suspiciously - gone. It does take away some urgency, though, and you can look around your room.

 The area around you is clean and well kept. On the dresser beside your bed is a get well soon card  signed by Myra and Arthur and including a handwritten apology from each.   

 Well, at least you know how you got here. 

 Next to the card is a basket of cookies emitting a very enticing smell... enticing enough that you feel your exploration is best put on hold in favor of finding a way over there. Though the gap would be a little wide even if it wasn't up higher than the surface of the hospital bed...

 Tentatively, you bounce on the bed. The mattress is rather firm, and you don't seem to have lost any of your – admittedly somewhat lacking – athleticism. Fortunately, you're still a rabbit, and being TOO terrible at jumping just isn't an option. You get a couple bounces going before jumping on top of the pillow, a plush disaster larger than you by orders of magnitude. You sink into it quite thoroughly, the weave of the fabric catching your toes, low threadcount leaving massive gaps at your relative scales.   

 Fortunately, it's a pillow, not quicksand. You pull yourself out and find a more stable point to gather momentum again, hopping up onto the headboard and marching to the far end, balancing along the iron bar. You take a deep breath, backing up, before running forward and making a LEAP onto the dresser... 

 You cough as you land. You sort of expected a melodramatic scrabble once you fell short, but your jumping height seems better than you expected.   

 You're still rewarding yourself with a cookie. Multiples even! You climb into the basket, snuggling up to the pastry. ...You admittedly aren't usually this addicted to them (probably) but you feel like you haven't eaten in ages. You start at the bottom of one, nibbling off a couple crumbs.   

 They're rich and doughy. Even at their excessive size the crisp outer layer is thin enough for you to deal with, and the interior is soft and eggy, without being overcooked. The chocolate chips are at least the size of your head, and you resolve to plow through until you eat yourself sick.   

 You make it through one chip of the cookie, feeling only relief from your stomach, you didn't realize quite how hungry you were... 

 You nipple off a corner close to the size of your torso. You think that eating that much probably means you'll vomit, but you can't resist.   

 You make it through... uh... half a cookie.   

 You realize that you shouldn't be ABLE to make it through half a cookie when they're that much bigger than you are. Standing next to the remaining half of the pastry you see that even half a baked good is as big as you are.   

 Which... you do some quick geometry (or perhaps just remembering)... is much smaller than it was.   

 Forcing yourself to slow down, you eat the rest of the cookie, every bite still as gooey and delicious... but also, apparently, VERY healthy.   

 You've always wanted an excuse to eat a basket of cookies and legitimately claim it's for your health.   

 Over the course of the second cookie, you start looking yourself over. The fatty sweet is certainly doing its job with your body type, your butt looking bigger proportionally than it was... but VERY tight and bouncy, moreso than it ever was before.   

 While you go through the second cookie, you start to play with your chest, giving your nipples a little tug as you enjoy the sensations. Something deep inside your brain is starting to wake up. A sixth sense, similar to touch but with a few distinct charms of its own... or possibly just a combination of regular touch with a new sense of narcissism.   

 Because while you go through the third cookie, you feel yourself grow. Even as you tug, you can feel your chest swelling out against your hands. You can feel your bones extend slowly, tingling as they climb rather than cracking or suffering. You can feel your heart grow three sizes, not more loving, but stronger and healthier, like an athlete watching over your expanding body.   

 Over the fourth you sit on the edge of the dresser, grinning as your feet dangle closer to the floor. 

 On the fifth you give careful pause to your paws, enjoying as the toes expand in proportion with the rest of you. Soon enough, they're so sizeable you could lose what you still think of as 'properly' sized tools between the pads. 

 While nibbling the sixth cookie you decide anything smaller than Myra probably isn't 'properly' sized at all.   

 For the seventh, you just stuff it all in, swallowing heavily and rubbing your stomach. Despite the richness of your 'diet', you can't help but lose babyfat. Your waist is skinnier than it used to be in relation to the rest of you, and you actually feel the beginnings of a tiny bit of muscle across your stomach.   

 For the eighth, you close your eyes and take a deep breath. The air swirling around inside you is moving so much faster, at so much greater pressure than it used to. You briefly wonder how you even can breathe at larger sizes. Your contemplation of the question is interrupted by a giggle when you realize how inevitable those larger sizes feel. 

 Over the ninth cookie, you try to lift up the basket. It's actually still a bit larger than you, but you feel incredibly energized. Your arms may be delicate and... honestly a tiny bit flabby... but you're sure you can pick up a basket of four cookies.   

 Myra makes baskets out of metal, you decide, since it turns out you cannot. You eat another one, however, and decide that you definitely can lift a basket of three cookies. This assumption is actually correct, though the fact that your arms no longer appear flabby in the slightest may have something to do with it.   
 
 You try to just appreciate the 11th cookie. It's a testament to Myra's skill or at least consideration that they still taste good despite the fact that they've had to be repurposed as ninety percent of your increased body mass. Either that or it's just the secret ingredient. You're currently assuming it's “love, and growth serum, but mostly love” and quietly hope you actually get that line.   

 On the twelfth cookie you try to measure your height by putting your hand atop your head. It doesn't really work when everything is growing proportionally, but your ears are perky and your bedhead isn't too bad and it gives you an excuse to look at your arms. You didn't think they'd ever be attractive but they're starting to get that way... 

 You eat the thirteenth and last cookie. Your proportions seem to be mostly stabilizing and you really want a mirror. Fortunately, you've gained enough height that that shouldn't be a problem. You climb down the dresser, now closer to an infant than a mouse in relation to the room. At the foot of your bed is a floor-length mirror, allowing you to get a look at yourself. 

 You look good. Not great, not yet, not after the people you've met, but you look good. Your curves are shapely and noticeable. Your proportions speak of somebody who is actually short, rather than just being on an altogether lower scale than your neighbors. Your chest is perky enough even without the hospital gown you didn't notice before now riding up hard enough to count as a tube top at best. 

 Most of all, though, you look in shape. Your fur is smooth, your waist is lean, and your muscles exist. You look like somebody who takes care of herself.   

 In a hospital, that's a very good look to have. 

 You take a deep breath and turn around to look at your medical chart, surprised to find it next to a set of marking's for height. 

 Your intake height was accurate enough, but what surprises you is your current height... 25 feet tall. A real giantess and you missed it because this hospital is so comical. You consider feeling cheated, before you realize something else. You were much, MUCH smaller than your original height SHOULD be compared to your current height when you woke up.   

 You pull down the chart, browsing it with greater fervor. All the usual data is there, blood type, weight, species, age... not a lot of medical history, though. That's good, it makes it easier to find the new data.   

 Metabolic Disorder: Macrocata 

 Not... really useful. Damn doctors and their buzzwords. Fortunately, you find a note attached to it.   

 “Hello dear! I hope somebody is reading this to you safely. I've brought some emergency calories to make sure you can hang on a while. You've got macrocata! A rare metabolic disorder...”   

 Arthur's different handwriting interrupts, “That is most certainly NOT my fault.” 

 Before Myra continues, “a rare disorder that causes your metabolism to swing extremely far both ways. 'Macrobolism' is a state where the body processes additional calories into greater all over size. Managing to induce it artificially is the topic of several entire industries around here. While catabolism is less unique to us, it's the body breaking down its own tissues for energy. Macrocata is a fusion of the two... you have an easy time gaining size, but an even easier time losing it. I advise trying to stay as healthy as possible! It's not really allowed for retirees like us to visit zones for smaller folks, so you may not see us for a while, those cookies may have to last...” 

 You feel a sinking feeling as you read your first companion in this world's last words. Now you're just... a patient.   

 You also feel a sinking feeling as you shrink slightly, a couple of inches already burning off of your body.   

 The loud steps of the doctor sound their way down the hallway, leaving you with a moment to think before you have to be a big girl and learn what's coming. 

 Though, you suppose, you are at least a BIG girl now.