My Job as a Model Patient

I received an email from Prof. Apple the next day, asking me to come to campus early before the next class.

When I showed up at his teaching lab, there was what looked like a covered body on the examination table.

"Aaron, yesterday was very good. The students liked you, and you were such a good sport."

"Thanks." I shrug.

"I do feel as if I blindsided you with our demands, so I wanted to go over the female anatomy doll now, its parts, its functions, so that you know what's expected of you during class. You may consider this a bonus session."

Extra money sounded good to me. I was fascinated as he pulled the sheet off the examination table to reveal...

... a weird ass anatomy doll. Transparent, yes, but you could see plastic lungs, a heart, organs - all the internals were different colors - like giant bubble wrap stuffed inside a see-through mannequin. The woman doll looked like she was made of clear plastic and latex. Prof. Apple opened up its chest like the hood of a car, so that he could remove some of the organs to show me. So creepy, each piece was soft and pliable - like the material the fleshlight was made of.

"Aaron, I want you to pay attention to this area." He pointed to the doll's vagina. "You can see that there's a full representation of the vagina canal to the cervix. The working theory is that when a male deposits sperm in a missionary position, semen pools at the bottom of the cervix. However, if you were depositing in a different position, the pool would be elsewhere. Different positions, different odds of fertilization."

The professor pointed at the bulge in my pants, "Good, Aaron, I see this is interesting to you."

I blushed and nodded.

"The doll is lubricated and equipped with 2 micro-cameras - one at the end of the cervix, another aimed at the vaginal canal so that we can watch your penis' motions. It also has sensors at the clitoris and along the vaginal wall so we can monitor when your movements are causing female stimulation. You will be inserting yourself in those 2 positions, depositing semen, withdrawing so that the students can watch the pooling." He points to two monitors on the table.

"Um, inserting myself? Depositing semen?" I scratched my head as I realized what he meant.

The professor walked around the table in a slow circle. "Just like yesterday, you will be stimulated to a point where you can deposit semen into the doll. This is a bonus situation where I can authorize $100 an hour."

"I don't know, professor. I'd be on this table having sex with this doll in front of the students?"

"No, not at all. You would be posing with this doll and depositing semen down its vaginal canal so that the students can observe coital optimization."

"But, I mean, isn't that what I just said? Having sex?"

"No, heavens no, Aaron. Sex would imply another living person. This is essentially a teaching aide, a doll."

Geez, I was trying to understand the difference. "So professor, I stick my dick..."

"You will insert your penis..."

"Into this doll..."

"Yes."

"And cum..."

"And deposit semen."

"In front of the students."

"Yes, and you'll be masked, don't forget. Just in case you're worried about anonymity. And you'll be paid more for this extra effort."

Ah, right. The money. "I'm not sure, professor. Especially if I have to do this for a couple classes."

"I thought you might have reservations, Aaron. So I wanted to prepare you. Take one of these pills," he handed me a little blue pill, "This is viagra. And I think a viagra for an 18 year old male will be very effective!"

I popped the pill even though I was already hard from looking at the doll's vagina.

"OK, Aaron, could you put on your surgical mask and undress? I want to bring in a student to work with you."

I obediently stripped to my birthday suit and put the mask on, my boner happily wagging in the air.

There was a knock at the door. In walked L. (my sister) wearing her surgical mask, surgical gloves and lab coat. My dick wanted to droop at the sight of her, but the viagra kept me firm and engorged.

Prof Apple smiled, "You remember, L.? She has kindly volunteered to help you work with the doll. For extra credit!"

Instinctively, I covered myself, but L. walked over and playfully grabbed at my dick, "You look ready!" she laughed. Why had I not recognized her voice before?

"So what L. will do during class is to help keep you stimulated in case the viagra fails. You put down on your employment form that you are heterosexual, so I wanted female hands for you. I realize this is an intimate act - even if it is with an anatomy doll, and especially in front of other people, so L. will be giving you, " he coughed, "any assistance required."

"What kind of assistance?" I was going to fuck the doll, what more did they want from me?

"Here, silly," L. says. She reaches to hold the base of my cock and expertly squeezes which makes my already erect dick look like it's Hulking deep red and veiny. "You're very lucky," L. says to me, "I've had lots of boyfriends and I know how to keep a guy hard." She giggles and I'm cringing inside that this is my sister holding me by the base of my dick.

"Now let me guide you," she giggles as she pulls me toward the doll, "and help you in there." She rubs the head of my glistening dick head against the doll's rubber lips. The doll's sensors beep as I hit the clitoris. Then she glides in the tip while I step closer to push my entire length in.

We all turn to look at the monitor and watch with interest to see the head of my cock pushing through and pulling back inside the slick plastic tunnel. I don't know what was hotter - watching myself, or watching the ribbed plastic tunnel massage the whole of my dick from head to shaft like some sort of organic car wash.

"Very good!" Professor Apple smiles. He steps closer to the table as we all admire my dick, alternately at the monitors and then down inside the transparent doll. "Now, young man, you must rock your hips in and out to simulate coitus."

Duh, no kidding, I thought. I can do this. I start rocking, but after 3 strokes, my dick slips out. L. quickly grabs a hold of me and guides me back in but after popping out 2 more times, the Prof points to L. who keeps a hold of the base of my dick while I pumped more slowly.

"How does that feel?" The Prof asked.

"Good."

"He's doing good." L. says, like some dick expert. I want to scream that my sister's lubed gloved hands felt really good holding my shaft.

"Good," the professor points at the doll's see-through organs. "You two must work closely together. When our young fellow is ready to ejaculate, we want him fully extended inside so we can watch the semen deposit."

I nod while I keep up my strokes, slow and regular, with my sister's hand holding my base firmly to stop me from slipping out. She suddenly uses her other hand to stroke my stomach, "Nice abs!" she says. I groan a little bit - this is the same sister who usually calls me monkey because I'm skinny.

"L! Please keep this professional! Our young man is already nervous enough as he is!" The professor snapped.

I'm pumping away at the doll, slapping my sister's hand against this artificial vagina. The viagra is keeping my dick superhard and I don't feel like I'm close to cumming at all. I watch the head of my dick ramming at the camera.

After 10 minutes, the professor asks, "Are you close?"

"Um, no."

"L. Could you digitally stimulate him please?"

"Sure!" And with that, she enthusiastically uses her other gloved hand and reaches between my ass cheeks. I jumped as she pushes in a finger and begins to wriggle it near my prostate.

The effect was immediate, I pumped faster and start to huff and puff. I feel a surge - I was going to cum soon. L. and the professor watched with great interest as my reddening cock was plowing away into the see through doll. On the monitor, my angry red dick head was charging hard down the tube at the camera.

"Good, lad! Now L. We want full extension. Young man, you'd better give us warning when you're close."

I watched my dick swell harder and grow. I felt like it was a foot long, it felt so good! "I'm close. I'm close. I'm going to cum!"

"Good! Good!" the professor cheers, "Go for it! You may ejaculate!"

"You've got this! You've got this!" my sister whispers hoarsely, one hand on my shoulder, one hand on my dick. How can she know that she's cheering on her kid brother's pumping motions? At that, L. holds my ass and tries to keep me in position deep inside the doll. I was covered with sweat as a I panted, hyperventilated. It was like I was being consumed by my orgasm. I wanted to mount this doll hard. I wanted the world to see how big and hot a load I could deliver. Then I shuddered as I shot my load and it was like an explosion of milky white inside the doll's organs. On the monitor, I was thrilled to see the head of my dick spit gobs of sperm. The doll's sensors was beeping - I think it came too!

"That's a lot of cum!" L. said.

I was in a post-cum rager - I kept pushing my dick deeper into the doll as if I wanted to push all the way up into its chest.

L. laughed, "Take it easy, stud. I forgot - this is the virgin boy's first time having sex!"

Prof. Apple smiled, "Well done, young man." He patted my shoulder.

Omigawd, I feel good. Standing there naked, sweaty, panting, strong, hands on hips with the pride that I had just fucked a girl (yes, I know, a doll) hard and came deep inside her. The professor and my sister cheering me on. I'm standing there dripping in sweat with my sister holding my still pulsing, still hard dick as residual cum oozing from my knob - I can see it on the monitor.

My sister smiles at me, not knowing my identity behind the surgical mask. Geez, can't she tell from my hair?

"Goodness, I forgot to get some towels for clean-up! I'll be right back!" The professor charged out of the lab.

L. looks at me as I withdraw my slick wet dick from the doll's vagina with a pop. I am still so hard that my dick is tapping up against my belly while my red cockhead is still dripping.

"Ooops!" my sister says. Then she pulls up the bottom of her surgical mask, and like yesterday, drops down to her knees and starts sucking me. The taste of my dick drives her mad. "Mmmm, so warm and salty. Virgin dick just came!" She moans while she sucks, giving me a hummer. I half close my eyes, enjoying her swallowing sucking motion as she expertly slathers my dick head and then tongues my shaft - it's like she's eating ribs.

She stops to glance at the lab door. Then she looks up at me, "You're still hard?"

I nod. If that isn't enough, she turns her attention to my balls, expertly mouthing them and then sucking them. But then she's back at my dick, licking the length, playing with my foreskin and then gobbling the head. "How can you still be hard?"

"Professor gave me a viagra," I explain.

"Omigawd, let's not waste it!" my sister hops up on the edge of an examination table, hikes up the lab coat and spreads her legs. Holy shit, she's not wearing underwear. She holds my erection and aims it at her own well-trimmed and pink vagina. "Come on, virgin boy, try a real woman!"

My stomach did flipflops at the sight of her. I couldn't fuck my own sister! I pulled out of her eager hand and away from her. I shook my head and started to look for my pants.

"What's wrong?" she asks.

"Um, I can't." I can't look at her. I'm looking for my clothes.

The professor walks in with a couple of white towels. "Here we go!" He immediately senses the tension in the room. He hands me a towel to dry off. I find my jeans and awkwardly try to zip up my boner.

"Is everything all right?" he asks. L and I are both silent.

The professor starts pacing around the lab, "I can't tell you how important these classes are. Human reproductive biology is important. And we are very lucky to have a young, healthy model patient. I can't tell you how difficult it is to get a volunteer to be so flexible and agreeable."

My sister nods her head. She's not happy at being rejected.

The professors turns to me, "Are you happy with the arrangement we have? Or would you prefer we find another model patient?"

"Oh, I'm good."

The professor smiles and slaps me on the back, "Good man! So looking at the calendar, we're going to have a couple of weeks with you and the female anatomy doll, depositing sperm in front of the lab groups. I can tell from some of the footage we captured today, that we're going to have some excellent results about sperm motility!"

I nod my head.

"And since you two are both here, I wanted to bring this up now for you to think about. End of semester, I would like to conduct a full coitus demonstration. L. here has already volunteered. I'm hoping our young man here will also agree. You will both be paid extra lab fees to have full coitus for the entire biology class."

Luckily I had my surgical mask on, because no one could see my jaw drop.

"Micro cameras will be set up inside L.'s vagina. We will also attach a endoscopic camera on your penis and watch actual human coitus from both inside the vagina's point of view and from the penis' entry angle. Isn't that exciting?"

L. clapped her hands and looked over at me. I didn't know what to do.

"Because of the intimacy involved, you will both be paid $500 for that session. You will both remain anonymous to each other and to the class - so keep those masks on!" He looked over at me, "Is everything OK, young man?"

I nod slowly. Shit, do I really want to fuck my sister for $500? Of course, we'd have our masks on. She would never know it's me. But I know it's her.

"He's just shy!" L. jumped in. "Professor, give me a month to warm him up in the lab and we'll be fine."

"Good!"

My sister suddenly leans in to whisper in my ear, "Hey virgin boy - we'll learn to fuck like rabbits and put on a show for class!" She reached out to stroke my abs but I grabbed my shirt and ran out.