Yerit peered at the amber serum in her hand, she'd handed over some good money for it and didn't want it to be a dud. The woman, Isis or something, that she bought it from smiled from under her hood
“Your natural enhancing stimulant is made from the best ingredients I can get, I assure you it works.” she cooed to Yerit with a smile trying to reassure her customer.
“Yeah... right, okay” she muttered, rolling the vial in her claws with thought “I already bought it so whatever” Yerit brushed it off quick to try and scoot out of the strange lady's heavily-scented shop. The whole place was packed to the brim with freaky plants and items made from said plants.

Yerit moved back to her isolated home away from people whose presence she only wanted to tolerate for part of the day, not most, the way she liked it. The stimulant was going towards something new today, something she decided to forget when talking to the shop owner today. She kept it held tight in her hand as she hopped up the stairs grabbing a red night gown from her bed and replacing it with her current clothes spare her undies, and a bottle from the bathroom before sliding her way back downstairs. Donning the nightie she brushed down the red fabric over her tail and buttocks making it straight, neat and comfy, just right, she placed the two bottles on the small table before her. One the vial with the stimulant in. The other a bottle of “Expecting Large” pills she had found advertised a few days ago. Her shoulders shuddered in excitement. She hated being so flat up and down, now she can get some weight to her but not just be carrying around extra useless tissue and it was gonna be fun. 

Removing one pill from the capsule she popped the cork on the serum and began slowly tipping the vial, holding it as steady as possible she watched intently as a single drop of the smooth amber stuff swelled beneath the lip of the vial before detaching itself from the main body and dousing the pill beneath it. Yerit placed the vial down again away from the pill. That was all she wanted, no reason to push her luck with anything at all.
Time to take the pill.
If her plan was right she'd still become pregnant with the one child, but the stimulant would help it grow and she get to have a big baby in a big belly. But now, pill in front of her, she didn't fancy taking it. This one little pill, it couldn't be right, there was something to be worried about, there had to be.
Oh yes! Yerit suddenly perked up, that's what was missing. Water. She didn't want to taste that pill on the way down, this was to be entirely pleasurable.
Retrieving the missing item hardly took a minute and she quickly followed it up with her pill and a swift swig of water, before jumping to the side of the table she dropped herself down onto her far-too squishy couch and waited. The Pill case promised a nice round pregnant belly in practically ten seconds! With a giddy grin on her face she traced her claws around her stomach in anticipation, only for her chest to draw attention first. A cold tingling sensation washed over her flat breasts only for them to be warm again an instant later. Shifting a claw underneath the red nightie it pressed into a dome of soft flesh that most certainly was not there prior to the cold sensation, pushing herself into a more upright position Yerit suddenly became aware of her chest becoming heavier quickly. The cold sensation prickled over her swelling mammaries again as they pressed out against the soft fabric of her gown, quickly grabbing the milk-laden breasts in her hands Yerit gasped as the cool feeling washed over her entire front and her body squirmed with the sensations wave. Her stomach was not going to be forgotten beneath the pleasurable breasts as it gave out a small growl and shuddered as it pushed against the deep red fabric surrounding it.
“Aaah ah! Yes” Yerit hissed through gritted teeth as her breasts were pushed upwards by her growing stomach practically creaking as it pushed out into any available space bulging out in some areas faster than others as if the developing child itself was pushing it outwards. From the time it had started growing, Yerit's stomach had only taken six seconds to balloon out to full term and keep going, the offspring inside kicked out as it began pressing up against the confines of her womb, growing into a weighty baby her large gravid sphere of a belly pushed Yerit's legs further and further apart forcing the one foot off the couch completely. Gasping in pleasure Yerit rubbed at the big sphere adorning her front through the snug nightie, within her the pup pushed back creating noticeable bumps along her front. The delicious tightness and wonderful movement within made her whole body quiver with joy, biting her lower lip the temptation was there. The bottle was right behind her and so was the water. The serum too. Just one large pup felt this great imagine the wonderful tight feeling of two, the amazing belly she'd have then! She felt herself get giddy at the mere thought. 
Weak to her desire for pleasure Yerit pushed against the side of the couch rolling herself onto her free leg but quickly dropped to her knees. Her belly was so heavy she could barely push herself up with this sudden weight but it barely mattered all she needed was to reach up and grab the three items from the table, within her the pup kicked about feeling just as energetic as mom.
Pouring out a pill into her hand Yerit prepped the serum for a second use but her hands shook far to much, groaning at the disruption  Yerit grabbed the pill and gently dipped it in the thin slither of amber fluid near the top of the tilted vial but paused. Before placing the lid back on she let out a single “Hah!” and dipped a third pill in and replacing the vial for the half empty glass of water and swallowing down both pills with an inane grin on her face and a rumble from down below. Rolling back onto her ass the night dress suddenly clenched round her middle as her gurgling stomach rippled outwards, the nightie was snug before but was now rapidly entering the tight zone and Yerit quickly reached for the hem to pull it up over her swelling middle but the fabric was already caught under her ass, and the sides split before she could even attempt to free it.
“Oh bugger” she let out in a breathy gasp as the tears grew wider accommodating growth spurt after growth spurt. Using her hands to prop herself up on the floor she had nothing free to reach up to her chest as a familiar cold tingle rolled over the leaking mammaries as parts began to slowly overflow the rim of the nightie
“I should've asked for the large nightie if I knew I was going to go for more!” she hissed as her stomach surged out with a creaking noise that sounded just like stretched leather. Pretty much pinned to the floor Yerit proudly wrapped her arms around her huge gravid sphere of joy proudly adorned with twin melon breasts it felt amazing, pure ecstasy. Now the only problem is how to get the three lil' pups to quit treating her insides as footballs.

You guessed that was going to be answered soon, as the instant the thought crossed your mind a deep pressure began to build up around your vagina which began to slowly leak fluids whining at the uncomfortable pressure Yerit pushed with all four limbs to try and lift herself and her large unborn pups off the floor in hopes of finding a better position and for panty removal. As soon as Yerit's ass was off the floor a floodgate of amniotic fluid came gushing out drenching the carpet behind her accompanied by a loud swear from Yerit. Pushing with her toes she forced herself onto her knees leaning against her gravid stomach for some extra support she desperately rubbed her belly trying to calm her triplets as they kicked out against her womb which began to steadily contract on them pushing the first down into her birth canal with enough force to make Yerit's entire body lurch forwards with a pained moan. The baby's head was certainly big it felt painful before it had even fully descended, attempting to lean back Yerit reached over to her twitching lips and slipped her fingers under her panties to check her dilation, at first it felt like only five centimetres but the rapidly increasing contractions seemed to dilate it further each time which was a miracle as with a horrendous screech of pain Yerit felt the first pup press against her exit eager to escape her cramped womb. Barely able to breathe Yerit snorted air angrily through her nose as she tried desperately not to push without some sort of 'ready' signal from her body which was becoming increasingly harder as pressure began to build up behind pup number one which only got worse as Yerit felt the second pup start heading down only to be blocked by its sibling.
“AAAAAAAAAAAAAA” Yerit threw her head back in a sudden sharp screech as the very instant the urge to push presented itself she bore down on the child at her lips, pressure releasing itself as more amniotic fluid poured out of her with force. No doubt about the childs size as Yerit heaved and strained with effort, drenching herself and the remnants of the nightie in sweat but with little avail. The moment she felt the pup start to emerge it reversed again. Yerit let out a whine of resignation. She'd have to do this twice again after the first one.
“Fuh! FUUUUUCKK MEEEEEEEEEE!!” Yerit suddenly spasmed as the next contraction spread her lips wide, the temporary relaxation in her muscles seemed to get the child moving as her vagina burned with fury crowning the first pup into her stressed undergarments of which Yerit could feel starting to roll ever-so-slowly down her legs as the emerging child pushed them off. Yerit pushed her hand past the contracting side of her stomach to yank on her underwear, pulling at it sharply she broke the string and let it flop to the floor accompanied by a horrendous wail from Yerit as without the extra little support offered by the fabric the pups head slid out accompanied by a torrent of fluids, straining with the fluids Yerit used it to her advantage and pushed down, hard, forcing out the first shoulder seconds after the head. Leaning back Yerit touched the cubs head gently against the floor before pushing with the next contraction forcing the next shoulder out. Yerit wailed as the cub shot out of her almost as fast as it grew within her getting showered with birth fluids as it flopped gently to the floor with a cry. Dropping onto her hands and knees Yerit tried to turn to reach for the crying infant but her second child was already beginning to crown clearly waiting right behind its older sibling, desperately trying not to push out the second before the first was taken care of. Rolling onto her side Yerit reached between her legs and lifted up a hefty baby... She glanced down, boy, up to her chest, the teal pup's cried quietened down with contact from his mother but with two others desperately trying to escape she could hardly coddle him much longer. Rolling over once more Yerit once more pushed herself to her knees and rested her elbow upon the couch and placed her keening son down upon a cushion. Using the couch as leverage she managed to stand herself upright with great effort, her chest heaved and sweat continued to drip from her, grabbing the glass she poured the last quarter of water over herself before sinking back down to her knees with the next contraction but at least now she had the couch to lean against.