Normally, Rocky hated waiting rooms. They were boring and uncomfortable, if there was a TV it was always on something awful, and it wasn't like anyone read magazines any more. The deer had nothing to do but sit and scroll on her phone any time she went to one of them, never knowing if it would be 15 minutes or 15 seconds before she had to stop whatever she was doing.

But this one wasn't so bad, considering that several of the people waiting with her, or those entering and exiting the back, had the kinds of figures she could only dream of having or playing with. Sure, a lot of them were normal, but now and then there was a man whose pants could barely contain the immense bulge at the front, or a woman sporting a cup size that would reach the far end of the alphabet. There was plenty of eye candy on offer, and her pink eyes eagerly followed the bouncing packages and the curves that put her own ample chest to shame.

She hoped she might end up like that, even if she hadn't come prepared at all. She was wearing a sleeveless denim jacket that was open over her black tank top, and a pink miniskirt with plaid patterning. Combined with her short black hair, styled upwards with red-dyed tips to look like a fire, she looked more ready for a hangout at the mall than a clinical trial at a pharmaceutical company shrouded in exciting rumors. Those very same rumors which, combined with the incredibly tempting cash compensation offer, had brought her here in the first place. She didn't actually know what trial #5425 entailed, but she was looking forward to finding out...

A fox woman in a plain blue shirt and pants came out from the back area, her own rack quite impressive in its own right, just less so than some of the other visitors to the building. Rocky was too caught up in admiring her chest enviously to realize the nurse was calling for her until the second time her name was repeated.

"Oh! Yes, that's me!" Rocky said as she stood up.

"Dr. Fang will see you now, please come with me," the nurse called out, and Rocky tried not to act too overly enthusiastic as she hurried over to where the fox nurse was waiting.

She could only contain herself for so long, however, and once she was being led through the much quieter corridors in the back, Rocky piped up, "So, what's this trial about? Am I-"

"I'm sorry, but I can't answer that," the nurse replied. "You'll hear all the details from Dr. Fang. She's just down the hall."

Rocky went quiet, her mind full of possibilities, so much so that she missed the fox turning into a room, and Rocky walked right past for just a second before noticing and doubling back. "The test subject is here," the nurse announced to someone inside, presumably this 'Dr. Fang' person Rocky had heard her mention.

Rocky caught back up and pretended like she had been there the whole time, but both of the others were facing away from her: Dr. Fang was a gray wolf with long gray hair, but beyond that Rocky couldn't tell much as she was bent over a computer in the corner and was wearing a labcoat that covered most of her body. "Thank you, Mindy, I'll take it from here," Dr. Fang replied, and Mindy turned to leave, her large breasts brushing against Rocky's as the nurse squeezed past her to leave.

Rocky closed the door and cleared her throat. "Um, hi, I'm-" she began.

"Rocky, yes," Dr. Fang replied without turning around. "Thank you for coming in and volunteering for the trial. We're always in need of more subjects, so if you do well enough here there might be some more work for you in the future."

More work meant more money, and Rocky briefly daydreamed at the thought of what she could do with it all. "Sounds good to me," she agreed, "So um, what do you need me to do? Is it a pill? Or an injection? I can handle getting a shot, but if it's some kind of medicine I hope it doesn't taste too bad."

Dr. Fang gave a little chuckle as she hit the enter key on the keyboard and then straightened up. "Oh, nothing like that," she began, "You see, the dose has already been administered... to me."

She turned around to face Rocky, whose eyes widened. Dr. Fang's labcoat was open at the front, with a black shirt underneath covering her breasts... and no other clothes. No pants, no skirt, and no panties, not that any pair of panties would have fit her considering that she had a cock that hung down to her knees, draped over a pair of gray-furred balls that were almost as large. Her dick was as thick as one of her legs, and it wasn't even hard yet.

Rocky's mouth hung open in surprised shock, but the way she was staring at it told Dr. Fang everything she needed to know. "I decided to... sample some of our recent treatments that have already gone through some of the phases of trials," she explained to the stunned deer, "And I was hoping you might be willing to help me test some of my new... properties." If Rocky had been paying more attention she might have been concerned by the grin that accompanied the following remark of, "In particular I want to try re-creating something a previous subject has been capable of doing... I'd normally have my interns help, but I need them to not be 'indisposed' for too long."

"Oh yeah, gladly! Whatever you say!" Rocky replied immediately, stepping closer for a better look. "So, uh, how do you want me? Up against the wall, or-?"

Dr. Fang chuckled and shook her head. "No, no, no... well... maybe later. I have other tests in mind first, though." Twisting her upper body, she turned to grab a clipboard from next to the computer, the movement making her cock sway a little, drawing Rocky's eyes to it. "I want to test my elasticity."

Rocky was snapped out of her admiration for the doctor's potent package. "Your, uh, what now?"

Pulling a pen from the top of the clipboard, Dr. Fang pointed with it towards her waiting cock. "You're comfortable using your hands, yes?"

"Hell yeah. I'd be a lot more comfortable with that thing in me, but I can do some foreplay," Rocky remarked with a keen interest, cracking her knuckles before reaching out with both hands.

Dr. Fang chuckled as she felt Rocky's hands grasp the underside of her shaft, hefting it and lifting it up. "For the first test I want you to insert your fingers into my urethra," Dr. Fang stated plainly, her tail was wagging behind her. "One at a time, please."

Rocky turned her gaze to the glans at the end of Dr. Fang's cock, sliding her right hand over to it as she knelt down in front of the doctor. The wolfess shivered slightly as Rocky's fingers glided over the sensitive tip, and Rocky pressed the tip of her index finger up against the opening. "You're pretty big, but will it really fit?" she asked, her left hand stroking back and forth over the underside of the hefty wolf cock, feeling it throb as blood flowed into it to start stiffening it up.

"There's only one way to find out!" Dr. Fang replied enthusiastically, pen held at the ready. "Previous data suggests that it should be quite easy, but such things must be verified through experiment."

"Well, all right," Rocky answered, and pushed at the opening. She was surprised at how easily her finger slipped into the opening at the end of Dr. Fang's cock, though the wolfess let out a loud moan and bucked her hips, taking the rest of Rocky's finger in up to the knuckle, while accidentally drawing a line across the paper and off the clipboard entirely. "Are you okay?" Rocky asked.

"Very much so, yes," Dr. Fang replied, taking a breath. "Do continue!"

Obligingly, Rocky wiggled her finger around inside of Dr. Fang's cumslit, making the doctor moan again. Her cock was rapidly erecting, growing in length though not in girth, and Rocky had no trouble inserting a second finger alongside the first. "Wow, you really are stretchy," Rocky observed, moving her fingers back and forth, still holding up the rest of Dr. Fang's cock as it stiffened.

"We will see just how much," Dr. Fang replied cryptically between breaths. Rocky kept going, working her third finger in, and then her fourth, wiggling them all around inside. Precum was starting to leak from the wolfess's member, slicking her fingers up – and then Rocky felt the walls close around her fingers and tug a bit, pulling her hand inward, her thumb slipping past the edge of Dr. Fang's urethra.

"Whoops, sorry!" Rocky replied in reflex, starting to pull her hand back, only for Dr. Fang's cock to resist, pulling on it.

"Don't apologize, this is... all part of the experiment..." Dr. Fang replied, her eyes half-closed as she stared absently at the clipboard, slowly and clumsily writing on it. "You are doing... very well."

"My hand is stuck, though."

Dr. Fang's lips curled into a smirk, something that Rocky missed as she was too busy staring at the bulbous head of the dick right in front of her. "Not to worry, it is an opportunity. Try fisting me and see if that works."

"Fist-?" Rocky started to exclaim, then looked at her wrist, already half-engulfed by Dr. Fang's shaft. "Yeah, it'll probably work! Let's try it." She curled her fingers into a fist, watching the bottom of Dr. Fang's cock bulge out as a result. She put her left hand over that bulge, feeling her own fist through the urethral walls, and grinned.

"Now just-" Dr. Fang began, but it was her turn to be cut off mid-sentence as Rocky pushed her arm inwards with a loud squelching sound as precum was forced out around her forearm. Rocky pulled her arm back despite the resistance of Dr. Fang's cock, and pushed it in deeper, grinning widely as she did.

"If all your clinical trials are like this, sign me up for more!" Rocky joked as she pumped her arm back and forth, making Dr. Fang's legs tremble as she gripped the computer desk behind her with one hand for support. Every time Rocky pushed her arm in, she reached deeper, and more slippery precum spilled out around her arm, some of it landing on the floor while the rest ran down the underside of the wolfess's shaft. It got harder and harder to pull her arm back the further she went, getting in past her elbow and eventually reaching all the way up to her shoulder.

After stuffing her entire arm down Dr. Fang's cock, Rocky's grin suddenly disappeared as she pulled back as hard as she could, but didn't get anywhere. "Uh, I'm stuck," she grunted, twisting and wiggling her arm while grabbing Dr. Fang's pre-covered cockhead to try and gain extra leverage, the motions only making the doctor moan louder still. The inner walls of that thick, throbbing cock weren't just resisting her, it felt like they were actively trying to pull her in. She eased the fingers of her left hand into the sucking urethra, trying to pry it off of her arm to no avail.

"Don't worry," Dr. Fang panted, "It's just... stage two of... the experiment!"

With a grunt of effort from the doctor, her cock suddenly pulled even harder on Rocky's arm, taking the deer by surprise. "Holy-!" she began as she was tugged forward, her other arm and her head both getting yanked inside with a loud, wet slurp. In reflex she kicked her legs and tried to wriggle free, but Dr. Fang groaned out and Rocky felt another strong tug that yanked her whole body inwards, engulfing her heavy tits and swallowing her all the way to her waist.

"Ahh, I see...!" Dr. Fang mused aloud between panting breaths, "I can control it like... this!"

Rocky stopped struggling, growing even more excited to see what happened next. She'd wanted that huge cock inside her, but instead, she was inside of it! As Dr. Fang moaned out, the urethral walls pressed in on Rocky from all sides, surrounding her like a tight sleeping bag, relaxing for just a brief moment. Then, Dr. Fang's next tug pulled her almost all the way in, slurping her up like a spaghetti noodle, and Rocky's outstretched arms were in some sort of an open space now. "This is amazing!" Rocky shouted, hoping Dr. Fang could still hear her.

The next time the walls rippled over her body to pull her deeper in, Rocky was pulled into Dr. Fang's sack, her hands pressing up against the bottom first. It seemed like it was one big hollow space, and as she was tugged in and gravity took over, the walls seemed to stretch out around her to make space – just not enough to allow her to stretch out. She fell in face-first to a pool of cum, and then tumbled inside as her legs were pulled in too, ending up in a sitting position with her knees close to her chest, covered in the cum that was all over the walls and partly filling the sack she was inside of.

"Ohh..." Dr. Fang moaned, her voice a little muffled to Rocky, still panting deeply. "This has been a... rousing success...!"

Rocky hummed in agreement, wiggling a bit inside of Dr. Fang's balls, reaching out and stroking at the walls with her hands, finding them wet and covered in cum. Sometimes they pulsed around her and pressed on her a bit, and cum sometimes dripped from the 'ceiling' and onto her. She reached between her legs, trying to lift her skirt, only to feel that it was already in tatters. "H-hey!" she blurted out, "My clothes!"

"Oh, yes, sorry about that," Dr. Fang consoled her from outside, "We'll offer extra compensation and a set of replacements. Don't worry, previous experiments have shown that it is... mmh... quite harmless to people."

Relaxing, Rocky leaned back against the back of Dr. Fang's sack. Experimentally, she pressed one foot against the opposite wall, feeling it deform around her a bit, then giggled and pulled her leg back. It was certainly a unique experience.

"How are you feeling in there?" Dr. Fang asked after a short time. "Do you want to come out?"

"No! I mean, yes I'm fine, but I don't want to come out!" Rocky quickly replied, shifting about as her right hand began idly fingering with her pussy under the surface of the pool of cum she was sitting in. "Can I stay in here for a bit?"

She felt Dr. Fang's hand patting her from the outside. "How long do you want to remain in there for?"

Rocky grinned in the darkness inside of Dr. Fang's balls. "How long can I stay?"

--------------------

Rocky moaned out as she felt the balls she was inside of swinging back and forth, splashing her repeatedly with cum. The fluid level was getting higher too as Dr. Fang continued doing whatever she was doing to get off, panting and moaning loudly enough to be audible to Rocky.

"Ohhh... finally... almost there...!" Dr. Fang moaned loudly, only partially drowned out by the churning sound that came from all around Rocky as her balls prepared to release.

Rocky was masturbating again, having lost count of how many orgasms she'd had while inside of the doctor. It had been an entire day since she'd been pulled inside, and she had loved the persistent warmth surrounding her. But all good things came to an end and now Dr. Fang was working on getting her out... in the only sensible way she had to empty her balls out.

"Yes... yes!" Dr. Fang shouted suddenly, and the walls around Rocky tensed hard, pushing against her as the sack she was in clenched. She was forced upwards and into the tunnels she had come in through, with a great amount of cum preceding her as well as pushing against her underside to add more pressure forcing her upwards. As she reached the base of Dr. Fang's cock she suddenly encountered some form of resistance, but it didn't last for long as those potent balls kept trying to cum, and there was a loud snapping sound before she shot through Dr. Fang's shaft, popping out of the end like a champagne cork. She landed on a pile of towels that had been prepared for her as cum showered all over her, the sudden light momentarily blinding her as Dr. Fang continued to cum, and cum hard; her orgasm lasted well over a minute, maybe even two, while Rocky lay there and panted heavily.

Eventually, Rocky rolled over onto her back and looked at her surroundings. She was somewhere in the pharmaceutical building, and Dr. Fang was slumped over some sort of breeding mount, though it had been split in half when Rocky had been forced through it and the ruined sleeve was torn open at the top to expose Dr. Fang's lubricant-covered dick. There was cum absolutely everywhere in front of her, and coating the floor thickly despite the drain in the center of the room. Rocky was drenched in it from head to toe, and the towels under her were totally saturated.

But Rocky still wasn't satisfied. Leaning back, she spread out her legs. "NOW will you fuck me with that monster?" she asked demandingly, wiggling her hips enticingly even as Dr. Fang stared at her in bewilderment.