The Fertility Experiment

"Well if you think it would help we can certainly try," Rachel said as she slipped off her lab coat and unbuttoned her cardigan. "I'm not sure this will do much though."

However as soon as she said it, she was surprised to see the beginnings of a reaction from Chris's penis. It began to twitch slightly and seemed to grow about half an inch or so. The reason for this was that Chris could now see the dark outline of her black plunge bra under her white blouse, as well as giving him a better idea as to the generous size of her bust.

"I can feel something happening Dr Addison," Chris exclaimed. "I am sure if you take off your blouse and skirt as well it will help even more."

"I can't do that Chris!" Rachel said in shocked tone "It wouldn't be professional and in my position..."

"But I am completely naked, and you would still have your underwear on," Chris countered. "Come on Doc I really think this would help a lot. Look at the response from just taking off your cardigan."

Rachel looked and sure enough his penis had swelled up to a more respectable size, about 6 inches in her estimation. However it still wasn't hard, so they couldn't do any further work just yet.

"OK Chris," She sighed reluctantly. "We will give it a try." She now wished that she had worn less sexy underwear to work, but then again she had never expected to be stripping off in front of her co-worker.

Rachel turned round, kicked off her shoes and undid the zip on the back of her skirt before letting it slip down her legs and stepping out of it. From behind Chris could now see the full length of her long shapely legs, as well as the creamy globes of her ass where they peeked below her blouse. He couldn't believe that his professor was wearing panties that were barely more than a thong!

There was now a fairly major reaction happening between Chris's legs. His penis has swelled to around 7 inches, which was normally his full erect size, but this time he still felt only half way there.

"Oh yes Doc, it is working," Chris shouted jubilantly. "Keep going, lose the blouse as well!"

Rachel looked round and was delighted to see a definite response from Chris's cock. She quickly unbuttoned her blouse and shrugged it off before turning round to reveal her bra covered chest to Chris in all its glory.

"Oh yes, yes, yes!" Chris moaned as he gazed at what seemed like acres of creamy white boob meat crammed into a tight plunge bra that seemed a size too small for her. He also took in her cute little belly and the tiny lace panties that barely covered her pubic mound.

Rachel came closer and subconsciously lifted her hands up to adjust her bra covered boobs, pushing her bulging mounds of mature flesh up and out of their wire and lace prison. Chris was sure he could see the edges of her areola peeking out from the edges of the straining bra cups.

"Wow Chris this really is working," Rachel gasped.

His cock was starting to rear up to a half erection without even being touched. He was now up to around 8 inches in length and had gained about 2 in girth as well. His testicles had also swelled up and were now much more noticeable, hanging loosely under his penis. Rachel looked at Chris's face and was a little annoyed to see his eyes glued to her boobs and a dreamy glazed look on his face. She knew she should be offended, but part of her was flattered that her 41 year old body could still have this effect on a young guy, even one she had dosed with a fertility drug. In fact she was even feeling a little turned on by the situation as she began to feel slight dampness between her legs.

"I think we might be able to get a sample now Chris," Rachel said, trying to bring Chris back to the task in hand. "Do you think you could produce one now?"

"I can't cum om command Doc," Chris laughed as he reluctantly tore his eyes from the splendour of her bra encased chest. "In face it might be better if you helped to extract the sample so it doesn't go everywhere."

Rachel was taken aback by the suggestion. Did he want her to wank him off! Her first thought was to refuse his request. However on further thought it might be better if she did it as it would allow a closer examination and better control of the subject. She also was beginning to feel more than a little excited by his now fairly hard organ and wanted to see how much bigger she could coax it.

Slightly tentatively Rachel took the swollen rod of flesh in her hand and slowly rubbed his foreskin up and down over the angry looking purple head. The second she touched it is seemed to grow about another inch and was now well over 8 inches in length and starting to get very hard.

"Oh Doc, that feels great." Chris moaned, as he threw his head back and lifted his pelvis off the table in an attempt to increase the pace of her stroking. "Keep going and I will cum in no time, I am close already."

It was true. Rachel could feel his organ swelling and pulsing in her hands and knew he didn't have long. With her other hand he reached down to feel his testicles which also seemed to have swelled up around 50% and were starting to churn uncontrollably.

"I think you have a nice load for me in here Chris," Rachel said, surprising herself with the slutty talk. "Give me a nice big sample."

This seemed to push Chris to another level and the churning and pulsing increased exponentially.

"Get ready Doc, I don't have long." He gasped through gritted teeth. Chris was a little ashamed just how quickly he was building to orgasm. He was not normally a premature ejaculator, but the drug and the fact it was Rachel masturbating him was pushing him to the edge far too quickly for his liking.

Rachel increased the frequency of her stroking with her right hand, while holding up a large laboratory beaker with her left to catch the sample. From the size of his balls she was pretty sure it was going to be a very large sample indeed.

Finally, after only a few more strokes, Chris began to moan uncontrollably and Rachel felt the twitching and pulsing from his cock and balls grow to a crescendo. Then suddenly he erupted, spurt after spurt of thick, white sperm shot out of the swollen head of his cock and into the beaker, which she was amazed to see was soon half full. After about 6 large spurts the flow began to slow a little but only after about 10 did Chris fall back onto the table, exhausted.

"Oh wow Doc, that was the most intense orgasm of my life, and the most cum I have every produced," Chris panted. "Your drug really works."

"Well, we will have to see about that," Rachel replied as she took the sample to the microscope, made up a slide and looked through the eyepiece. "You certainly have the quantity, but what about the quality?"

She was amazed by what saw. The number of live motile sperm in the sample looked about 3 times that of Chris's original sample, which had been pretty decent anyway. The drug would be life changing for men with low sperm counts, and finally allow them to father children, but for someone like Chris with a healthy sperm count it pushed his fertility through the roof. He could probably knock up a 70 year old with what he had just produced.

"This is great Chris," Rachel said excitedly. "The experiment has worked better than I could ever have anticipated. This will be career changing for both of us."

"E,h great Doc," Chris replied, sounding a little worried. "However I still have a little problem over here."

Rachel turned round and was surprised to see that Chris's erection had only gone down slightly after his orgasm. He was still around 8 inches in size and his cock looked very red and uncomfortable.

"Don't worry Chris, I did expect this," Rachel reassured him. "One of the side effects of the drug is increased length of erection and multiple orgasms. Also the 3 doses I gave you may have been a little too much."

"Well, can you help me out again Doc," Chris pleaded with her. "My balls still feel really full and that first orgasm just seems to have made things worse."

Rachel laughed. Now she knew the drug worked she was much more relaxed and was actually beginning to feel a bit horny herself. The dampness between her legs had increased to a small wet patch. Suddenly the realised that the overdose of ADIFEM she had taken that morning was reacting with the scent of Chris's ADIMAL laced semen, increasing her own sex drive to levels above even its normal high level. She knew she was losing her professionalism rapidly and would soon be in danger of becoming controlled by lust.

"I have to be careful here," Rachel though to herself. However she was also feeling quite playful and wanted to fully test out her new ADIMAL fuelled sex toy.

"OK Chris, I will give you a hand," She replied in her best low and sexy voice as she sauntered over to him. "How about we raise the stakes a bit? I want to see just how big you can get, and how big a sample you can give me.

Then to Chris's complete surprise she reached up and clasped her huge boobs with both hands pressing hard and forcing about half of her creamy mature flesh out of the skimpy plunge bra, exposing the edges of her areola. Immediately Chris felt his cock start to fully harden again as he gazed at her wonderful chest.

Then Rachel reached up and slowly slipped the straining bra straps down of her shoulders before lifting her arms out. Now her tight, bulging plunge bra was only held up by the tension of the clasp behind her back. With a sexy smile at Chris she slipped both hands round her back and flipped the clasp open. The straining cups fell away, revealing her magnificent chest in all its glory. Chris's cock gave a huge twitch and it rose up to an even larger erection than the first time. He was now close to 9 inches in length, with an even greater increase in girth.

Rachel's breasts were everything he had dreamed about for all those years. They were pear shaped with large areolae and big, hard, brown nipples. Her skin was a creamy white with a scattering of light brown freckles. Chris reckoned they were at least an E cup and due to their enormous size they sagged quite a bit now the bra was off. However, for a 41 year old woman you had to expect that. In fact the sag made them look even better to Chris, with his love of busty matures.

"I see you really like these," Rachel said playfully, as she lifted and massaged her boobs with her hands, before bringing each big brown nipple to her mouth and giving it a quick suck. Then she climbed on the table and scooted up so her heavenly chest hung just above Chris's now fully erect and twitching penis.

Then without another word she pressed her enormous tits together to form a wonderful prison of freckled mature boob flesh and clamped his cock in the middle. Chris felt his entire body shake as his cock was enveloped in her soft, hot cleavage and Rachel knew she had found his weakness.

"You really like this don't you Chris. My boobs are so big and soft, not bad for a 41 year old are they?" she moaned softly. "I can feel your cock getting bigger and bigger. I can feel every twitch and throb of your heavy sperm filled balls. I bet they are still full with all that ADIMAL I pumped into you. I want you to spurt a big load of cum all over my tits. I am sure you can produce an even bigger load than before."

Rachel was surprising herself with all the dirty talk as she had never done that before. The rational side of her brain told her that the cum that was already leaking from Chris was being absorbed by the skin of her chest, and the ADIMAL in his semen was reacting with the excess dosed of ADIFEM she had taken that morning, pushing her sex drive into the stratosphere. All she knew was that it felt amazing.

Rachel began to slowly slide up and down, rubbing his cock between her heaving boobs. When the sensitive throbbing helmet of his cock emerged on every few stroke she lowered her mouth and gave it a quick suck, which almost sent him over the edge each time she did it.

"Oh, Ah, Doc slow down," Chris gasped. "Your tits are too good. I won't last another 30 seconds if you keep this up." Chris couldn't believe the effect she was having on him, and was mortified that he wasn't even capable of lasting 1 minute under her ministrations.

Rachel just gave him an evil smile and increased the pace, pushing her boobs tighter together and increasing the speed of her up and down motion.

"Oh Doc, please slow down I can't hold on, If you don't stop I will cum all over you!" Chris pleaded once again. His cock still seemed to be growing and must have been over 9 inches as it slid in and out of the soft heavenly valley of her boob flesh. He felt his balls begin to throb and churn again, as did Rachel, but instead of stopping and moving away she just pressed even harder and moved even faster.

This was more Chris's poor drug stimulated cock could take. With a cry of anguish he felt the first uncontrollable pulse from deep in his balls as they tensed up to release their second load of super potent seed. He felt cum ripple up through his quivering member and exploded through the swollen tip, all over Rachel's face and tits. Instead of moving away, Rachel kept on squeezing him, as if to wring every last drop of cum from his now enormous balls. His orgasm seemed to last even longer this time, with over 12 huge spurts of semen bursting from him and completely covering Rachel's chest in his seed. As his orgasm subsided Rachel even opened her mouth and caught the last few spurts on her tongue.

Rachel was delirious with lust. Her lacy panties were a sopping mess with her vaginal juices and her clitoris felt on fire. She thrust a hand down the gusset of her panties and started rubbing frantically, but it wasn't enough. The ADIMAL infused cum that coated her tits and was now in her mouth caused a chain reaction in her own drug augmented system. But it still wasn't enough. Now completely out of control she jumped up and frantically searched through one of the drawers in the lab.

"What are you doing Doc?" Chris asked as he collapsed on the table and tried to recover from his monumental climax. He was amazed when Rachel brought out a pack of 7 ADIFEM, which should be a week's supply, and popped all 7 into her mouth at once. With the 3 she had already taken that morning she now had 10 times the recommended dose in her system.

"Doc, what are you doing, this is dangerous, that is too big a dose," Chris warned. "We don't know what that will do to you."

"I NEED MORE!" Rachel screamed and jumped back on the table. Chris's penis was still hugely swollen at around 9 inches and still hadn't really gone down after his second orgasm, but it still wasn't enough for the now lust blinded Rachel. To Chris's horror she reached under his massive balls and pulled the toggle on his cock ring as tight as she could. The veins at the base of his penis bulged out and before he could stop her, Rachel grabbed both the two remaining syringes of ADIMAL and injected both deep into the base of his cock at once.

"Doc what have you done!" Chris gasped in horror. However he didn't have much time to think about is as the drug kicked in instantly and he felt his cock begin to expand once again, as a feeling of lust like he had never felt before hit him like a tidal wave.

"Oh yes, bigger, bigger I need it bigger," Rachel moaned as she began rubbing Chris's cock again. It was now around 10 inches and growing fast. "Please get bigger, I need more" With that she locked her lips round the swollen helmet of Chris's now monstrous penis and began sucking any pre cum and semen that was still there from his last orgasm into her mouth. When she had got all of it, she released him from her mouth and started to frantically tit fuck him again, even harder and faster this time. She was desperately trying to increase his size even further, force him to yet another orgasm and extract even more semen. And it was working.

The overdose of ADIMAL was causing Chris to lose all sense of control. He looked down at his cock which by now was close to 12 inches size with his balls the size of large plumbs. Even with her enormous tits his cock no longer looked dwarfed by them as she thrust it in and out of her hot and tremulous cleavage. He knew he had another, even bigger, load bubbling away in in his balls, but he didn't want to blow it impotently on her boobs again before he had the chance to actually have sex with Rachel.

In an attempt to take some charge of the situation Chris grabbed Rachel by the shoulders and pulled her face close to his so he could give her French kiss, the first time he had actually kissed her in the entire encounter.

"Doc, please let me have sex with you properly," Chris pleaded. "I really need to get this big cock inside you. I know you would enjoy it too." Chris reached down and stuck his hand inside Rachel's now soaked panties, searching for her clit. It wasn't hard to find. Her pussy lips were shaved and her clitoris felt hot and very bloated under his probing fingers. As he made contact he felt her whole body quiver, and he knew she was close to orgasm as well, despite him not touching her until now.

"I would love that as well Chris," Rachel moaned in response. "It would be too dangerous though. We are both so fertile just now and I can't risk getting pregnant."

Even in Rachel's drug induced state the fear of pregnancy still cut through. At 41 she had no plans for children now or in the future, even with access to her miracle fertility drug. She was so focussed on her career she had never even really thought about it.

"I will use a condom Doc," Chris said, trying to reason with her. "When I am close I will pull out and cum on your boobs like before, or in your mouth. Please Rachel I really need this."

This was the first time Chris had ever used her first name, and somehow this made a difference to Rachel. She wasn't happy about having sex without her diaphragm in, but if they used a condom and he pulled out then that should be ok. In the end her rampant, drug fuelled desire got the better of her.

"OK Chris, but you have to pull out before you cum." She said reluctantly. "With you being so big now I don't know how well a condom will hold up."

Chris could not believe what he was hearing. This was really happening. He was actually going to fuck Rachel. Well, more likely she was going to fuck him if their sexual encounter so far was anything to go by. He reached for his discarded trousers and removed a condom from his wallet. He struggled with the wrapper with trembling fingers before carefully removing the thin latex disk.

Rachel was slightly worried to see he had a durex invisible extra thin condom, and not the extra strong double thickness ones that she always used. However beggars cannot be choosers, and as long as he pulled out it would be fine. He had already ejaculated twice so surely he couldn't have much more in there?

Rachel took the condom from him and placed it on the on the tip of his now 12 inch weapon. She struggled to squeeze it over the bulbous swollen helmet and had to spit on it to provide enough lubrication but after that, with a few strokes, she had the thin, straining latex sheath rolled down all the way to his balls.

Rachel sat on the table beside him, looking at his enormous, potent weapon, wrapped up snugly and (hopefully) safely. The condom looked very thin and fragile, moulded to every vein and ridge of his throbbing manhood, and she still had her doubts about it, but before she could say anything Chris lifted her on top before grabbing her now ruined and sopping panties and ripping them off with one swift stroke. Her pussy was neatly shaved with only a small landing strip of hair. The lips were meaty, succulent and very wet. At the junction of pussy lips her clitoris was huge, standing out about 2 inches, and looked very inflamed and angry. All in all, it was the best looking pussy Chris had ever seen, and he couldn't wait to get inside it.