Tina was one of those special people in the world who loves to help others. She had been a nurse for more than twenty years, and at age forty five, still volunteered for a number of health related studies. It had been six months since the last time she had volunteered for one of these studies. It was a sexual health study of middle age women. The idea of the study was to see if women were more or less aroused when they hit middle age. The study involved Tina having sex with a young man, who had a ten inch cock. They wanted to see if a bigger cock really gave women better orgasms or not. The study also included a new drug that helps women get more aroused.

Tina and her husband Mark, who had watched on with several other medical students, were amazed how aroused Tina had gotten that day. Tina came several times, while taking on the young man’s huge cock. The study was quite a success, and Dr. Gundy now had more money to push on with more of his studies. It took him years to persuade the board to give him the necessary funds to complete what he had thought was a viable cause.

Dr. Gundy had been searching for another participant for his next study. This study was a bit unusual, and he couldn’t divulge to the potential participants what it involved. If they agreed to do the study, they would be under his control, and would be required to do whatever he asked.

Dr. Gundy had received a number of interested responses, but so far no one fit what he had looking for. When Tina heard this, she immediately volunteered herself for the study. Dr. Gundy knew Tina would be a perfect patient like all the past times before, but this was a different type of sex study. He didn’t know if Tina would make a good fit or not.

One afternoon Tina pleaded with Dr. Gundy, “I know I can be a help.”

“Tina, you have no idea what this study consists of. I can’t go into great detail because it is very secretive, but I know you, and I wouldn’t want to see you do something you normally wouldn’t do. Besides that, your husband Mark can’t know a thing, and he won’t be able to be involved like the last study. ”

“But Dr. Gundy, I know I can do it, and you desperately need someone. Please give me a chance!”

Dr. Gundy sat back in his chair, and thought it out for the next few minutes. Tina was right, he so far didn’t have a worthy candidate for his study, and he knew Tina would make a perfect fit for it.

“Alright Tina, if you want to volunteer for this phase of the study then I will count you in, but remember your husband is not to know, and trust me, this study is very different from the last one. I need you to take home this survey and fill it out. I need it to be filled out truthfully.”

“Thank you Dr. Gundy! I know I will make your study a positive success.” Tina replied back.

Dr. Gundy then made it clear to Tina that she would need to do whatever is asked of her, along with taking a stronger amount of hormones. She would need to abstain from sex for thirty days, and take another trial medication. She could not say a word to her husband, and then report back to him in a month. Tina was okay with everything the doctor had asked of her. She was to keep a journal once again for the next month.

Tina felt a bit of guilt over the next few days. It hurt her not to be able to tell her loving husband Mark of almost twenty years about the new study, because of its secretive nature. She did as told, and kept a journal over the next thirty days. She abstained from sex over that period, even though she was more sexually aroused than any other time in her life. She gave her husband a number of excuses on why she couldn’t make love to him.

The thirty day period finally had come to an end. She reported back to Dr. Gundy ready, and extremely willing to be part of his study. Dr. Gundy reminded her again that she would need to do whatever is asked of her, and Tina responded back, “Don’t worry, I will do whatever you ask of me.”

“That is great Tina. Are you ready? How aroused are you feeling?” Dr. Gundy replied back.

“Very aroused! Those pills you gave me are way more potent than the last ones I took. I am aroused all day long.” Tina said to him.

“Ok Tina, here is the place the study will be held at. It is a research location about twenty minutes from here. I want to see you there tomorrow afternoon. Ok?”

“I will be there,” Tina replied back.

The next day Tina felt abnormally horny. Her pussy was extremely aroused, while moisture dampened her panties. She drove to the research facility all alone, and wondering what the study would consist of. She met Dr. Gundy in the corridor, and was led down a dark hallway to a room. Inside the room stood a bed, along with a wireless monitoring device. His assistant wired several wireless probes onto Tina’s body. This way the doctor would be able to monitor her heart rate, along with a few other vitally important things.

The doctor then advised Tina to get fully undressed. He would monitor everything from the room next to hers, leaving her all alone for the next few minutes. She then heard Dr. Gundy come across the audio system. Tina sat patiently on the bed, she was naked and extremely nervous. The lips of her pussy were covered in moisture, while she wondered what the study consists of. Dr. Gundy still didn’t tell Tina what the study had detailed.

Dr. Gundy had his own personal study he wanted to try. He wanted to see what happens when you mix two people that dislike or even hate one another into a room for the purposes of sex. He wanted to see if the adrenalin rush and the anger that they each felt for each other can produce significant and powerful orgasms between them.

Tina sat there almost stunned. She wondered why the survey wanted to know anyone that she despised. Tina loved almost everyone, though she did list a few people that she didn’t like a whole lot. One was a fellow employee, another was an associate that her husband worked with. She had listed a few others, but her list was just a very few.

A few minutes later the door to Tina’s room opened. She sat there extremely nervous and aroused when a familiar face walked in. She never imagined they would have chosen this individual, and now she was stuck in a particular weird situation. It was her daughter’s ex-boyfriend Derrick, who her daughter dated several months earlier. Tina hated Derrick with a passion, and told him to stay away from her eighteen year old daughter after finding out they were dating. Derrick was older, and at twenty two had no real future ahead of him. He had tattoos all across his body and loved to ride motorcycles with his friends.

Tina had seen a number of individuals hurt on motorcycles in the past, and certainly didn’t want her only daughter to be one of them. Tina never liked Derrick the first time she met him, and that still held true today.

“Derrick! No way!” Tina yelled out while trying to cover up her naked body with her hands.

“Tina, remember this is very vital for this study. You agreed to do it,” Dr. Gundy said across the audio system.

“I bet you never expected to see me walk in, did you? This is going to be fun fucking you senseless,” Derrick said to Tina.

Derrick also had wireless probes on him, and the hope was to follow his reactions just as well. Derrick began to undress in front of Tina. He had removed all of his clothes except for his briefs, while his huge cock pushed outward against them. Derrick was being paid a token amount for his involvement in this study, but he would receive a bonus for every time he could make Tina orgasm.

Derrick felt an extreme rush of adrenalin as he walked over toward Tina. Tina’s heart rate began to explode while Derrick got near her. When he got over to the bed he pulled Tina’s arms away from her beautiful tits, exposing each of them. His hands gravitated down toward each of them, while an angry Tina sat on the edge of the bed.

“Oh fuck your tits are so nice!” Derrick said to Tina.

Derrick took charge almost immediately as he made Tina lie across the bed.

“Spread those legs!” he demanded.”

Tina lay there with an extremely dirty look on her face, and slowly opened up her legs a few seconds later for the young man. Her pussy was so aroused, and now moisture dribbled down each side of her legs.

Derrick now got on top of her, and before Tina knew what had hit her, Derrick pushed his big thick cock deeply into her aroused pussy.

Tina fought back hard not letting Derrick know how much she was enjoying it. She tried in vain to reign in her emotions, while Derrick pounded his cock hard into her.

Several minutes had passed when Tina felt a powerful wave of energy come over like none ever before. Her body began to tremble hard on the bed. Derrick now had pushed every inch of his thick cock deeply into her.

“You want to cum baby!” Derrick shouted out.

Tina was helpless now, and just a minute or so later her body began to squirm hard on the bed. Her arms shot around Derrick’s young hot body, while she draped her legs tightly around his waist. She no longer could hang on, and seconds later she let out one of the most intense cries of her life. She began to cum hard all over Derrick’s thick cock sending her into an earth shattering experience.

“Did you like that baby?” Derrick asked a minute or so later.

“Now turn over, and get onto all fours for me!”

Tina flipped over onto her stomach. She then raised her ass back toward Derrick’s throbbing cock. Derrick then held tightly onto each of Tina’s hips. He forced his thick cock back into Tina from behind as Tina let out another loud cry.

Derrick now felt a sense of aggressiveness, and now began to pound his cock deep into Tina’s wet pussy. The sound of Tina’s cries filled the small room leaving Tina in a sense of utter denial. Derrick then grabbed the back of Tina’s hair, and pulled her body up from the bed. He now turned Tina’s head sideways, and slammed his tongue into her opened mouth. He felt the vibration of Tina’s body ripple right through each of their mouths. He began to taunt her, “You like the way I am fucking you bitch! Tell me?”

A few minutes later Tina felt another earth shattering orgasm building inside her. Her body began to squirm hard, and she was on the verge of cumming once again.

She began to scream out, “Give it to me! Give it to me!”

Derrick now gave Tina the fucking of a lifetime. He gave her several hard thrust with his thick cock sending Tina over the edge. Her orgasm was so powerful, and extremely intense that she no longer could stay up on all fours. Her limp body had fallen harmlessly down onto the bed, leaving Derrick with a huge moral victory over her.

“I am not done with you yet!” Derrick shouted out.

He now straddled his cock over top of Tina’s gorgeous ass. He lifted Tina’s ass slightly up off the bed, and pushed his thick cock back into her once again. He fucked her long and hard, giving it to her while she cried out in extreme pleasure.

A few minutes later, Tina again screamed out into another extremely intense orgasm. Her body shook hard, while Derrick’s orgasm was coming on quickly. Then a minute or so later, Derrick suddenly yanked his cock from Tina’s swollen pussy.

He cried out, “Oh fuck baby! I am going to cum all over your ass.”

Seconds later Derrick began to grunt out loudly. He started to shoot several streams of cum all over Tina’s quivering ass.

“Oh fuck that was good!” Derrick moaned out while the last drop of cum fell from his spent cock, and down onto Tina’s ass.

A short while later with Tina still aroused, and extremely vulnerable, Derrick said to her “I want you to touch yourself.”

A few seconds later, Tina slipped her hand down in between her legs. She felt a wave of energy come over her, as her body nearly jumped off the bed. Her pussy was still extremely swollen, and the lips of her cunt were puffy and extended out. Her clit throbbed with excitement once again, while she ran her hand gently back forth across it.

“I want to see you cum for me! Do it!” Derrick demanded.

Tina began to masturbate in front of Derrick. She had one finger in her swollen pussy, while she ran her other finger across her aroused clit. It didn’t take very long of touching herself when she felt a massive amount of energy come over her. Her body began to squirm about the bed, and she began to cry out, “Oh god! Oh god!”

Seconds later she had one of the most intense orgasms of her life. Her body shook for a good couple of minutes, while her juices ran down both sides of her legs.

“I think you liked that, didn’t you?” Derrick said to her.

Derrick then pulled Tina’s body over to the side of the bed. He stood at the side of the bed, and threw Tina’s legs high up over top each of his shoulders. He immediately pushed his cock back into her, and now had control over her once again. Tina didn’t like it one bit, and she didn’t want to give Derrick anymore satisfaction than he already had. She did her best not to allow him to dominate her any longer, but that changed just a short time later.

Tina’s body began to tremble hard on the bed. Her lovely big tits were now bouncing in a circular motion, while she did her best to keep her emotions in check, but that rapidly was coming to an end. Derrick then grabbed Tina’s legs, and pushed them back toward her head. He began to pound his cock deep into her, while he moaned out, “I want to hear you cum again!”

“No! No!” Tina desperately cried out.

It was now out of Tina’s control, and minutes later she no longer could take it. She began to scream out into one of the most fulfilling orgasms of her life. Her screams filled the small room, while her body shook hard on the bed like never before.

Derrick then flipped Tina over onto her stomach. Her legs hung over the side of the bed, while Derrick stared down at Tina’s lovely ass. His intention now was to fuck Tina in the ass. He pushed his cock up against her tight ass and with one hard thrust his thick cock slipped deeply into Tina’s tender ass. She immediately cried out, while she pounded her fists down onto the bed. She turned back toward Derrick and said, “You fucking bastard!”

Derrick now gave Tina’s ass a pounding, and that only infuriated Tina even more, but minutes later Tina began to moan out loudly. Her disgust for Derrick had changed once again, and she quickly felt an explosive orgasm coming on.

“You like it in your ass Tina? Tell me!” Derrick said to her seconds later.

“Oh god! Oh my god!” Tina yelled out.

She no longer could take it, and a minute or so later she felt a huge amount of energy begin to build inside her. Derrick now gave it to her good and hard, and this pushed Tina over the edge once again. She screamed out into one of the most intense orgasms of her life. Her body shook hard on the bed, while Derrick buried his thick cock deep into her tender ass.

A few minutes later, Derrick flipped Tina back over onto her back. He once again gave it to her hard, causing Tina to cry out once again in total pleasure. He had pounded his cock hard into her for a good ten minutes or so when he suddenly yanked his throbbing cock from her worn out pussy.

He held tightly onto his cock as he said to Tina, “Get down on your knees!”

Tina slid off the edge of the bed, and was positioned right in front of Derrick’s swollen cock. Derrick then grabbed the back of Tina’s head and gave his cock several hard thrust with his hand. He then moaned out to Tina, “Open up your mouth!”

Tina opened up her mouth just enough, and seconds later with Derrick’s cock only inches from her mouth he began to shoot several streams of cum into Tina’s opened mouth. Tina was now exhausted and finished. Derrick stared down at her, while an embarrassed Tina had cum dribbling from both sides of her mouth. He stood there like he was a king, conquering Tina into several powerful orgasms.

A few minutes later he grabbed his clothes, and left the room. Dr. Gundy walked in right after that, and said to Tina, “Wow! That was intense!”

Tina looked up at him and said, “Did you get what you need for the study?”

“Oh yeah, we got a lot of data. This backs up the notion that two people, who might hate each other, and have sex are more likely to have sex that will be much more intense and powerful. We got data from the two of you that blew away the data from the last phase. You have been a huge help in understanding the human body. I can’t wait to get the data from phase four. That should tell us even more.”

Tina, now went home that day knowing that she had helped out the medical science field, but also knowing that she had to fuck a guy she truly hated. She now wondered what phase four detailed, and if she would volunteer once again.