Biology Class

As Sarah entered her biology class, she noticed that the set up was different from her previous school. Each seat was filled with two students each. Every boy sat in one of the seats and every girl would sit in their lap. All of the chairs were already filled with one person so she looked around for a place to sit. Finally, she settled with a guy with a rather large cock. She could use some more hard fucking and add some more seed to the mix.

"Hey, is this taken?"

"Oh no. It's free"

Sarah faced the board and sat down, his erect cock sliding all the way into her pussy with ease. She slowly moved her hips back and forth, the cock mixing all the cum stuffed in her pussy.

The teacher got up to face the class. The women's teaching uniform was essentially as skimpy as the girl's uniform, only that the skirt and top were black, and they wore thigh-high black stockings. Like every other girl in the room, cum was sliding down the woman's thighs.

"Welcome everyone to finishing school, I'm Ms. Williams and I will be your biology teacher this semester. Everyone here is going to enjoy their time here"

"Today's class is going to be quite simple. We will be performing a lab experiment, and all you will need to do for today is follow the instructions. Now first of all, is everyone not sitting with someone of the opposite gender?"

She looked around and saw no one respond, as every girl was sitting with a guy.

"Very well then. Today's experiment will relate to sperm, specifically, its temperature. Sperm has a higher chance of impregnating a female when it is of higher temperature. What you all will be doing is extracting cum from a male through different methods and measuring its temperature."

"First, if you are a girl, you will jerk off the boy's cock until he cums, making sure to collect the sample in this beaker. Right away, you guys will stick a thermometer into it and record the temperature after 30 seconds. For the second time, you will suck the boy's cock until he cums in your mouth, after which you will spit it out into the beaker. The third time, the boy will fuck your pussy until he comes inside. You will place the beaker underneath your pussy to collect any sperm that drips out, and measure the temperature. Any questions?"

"Okay, also, since you all are already fucking, make sure to let the guy cum before performing the first trial. Then you may start"

Everyone began fucking their partners without restraints. Sarah bounced up and down on the boy's long cock while he squeezed onto her boobs from under her top, transparent from sweat and cum. Soon enough, he came inside, depositing a load of cum into her. Within seconds of slow thrusting, his cock was erect again. and Sarah got off. She began rubbing his cock, well lubed from pussy juices and cum.

The guy cummed and Sarah aimed his twitching cock into the beaker. The guy grabbed the thermometer and stuck it into the beaker.

"87 degrees," he said. Sarah wrote it down.

Sarah bent forward and began sucking the boy's cock, moving her head back and forth. Not long after, the guy cummed again, overflowing her mouth. Sarah spit out some of his load into another beaker while the guy measured it.

"90 degrees. Time for the main part"

After Sarah stood up, he spread apart her legs and pulled her onto his cock. Sarah hovered in the air as the boy thrust hard into her, hips swaying back and forth. Sarah yelped with pleasure as she felt the tip of the guy's cock touch her cervix with each thrust. She climaxed and squeezed her legs around him. The guy responded by pulling her down hard to the base of his cock, and cumming, his cock shooting jets of hot cum right against her cervix. Her pussy already stuffed full with his large cock and with not enough space for the guy's huge load, the pressurized cum rushed out from the sides of her pussy with great speed.

"Oh my god" she moaned.

The guy pulled her up and allowed the remaining cum to drip into it before measuring the temperature.

"95 degrees!"

Data collected, they continued fucking once again.

All the pairs soon reported the results to Ms. Williams.

"Before we leave, let us go over our results. The average temperature of cum through masturbation was about 88 degrees, through giving head was 90 degrees, and through penetrative vaginal sex was 94 degrees. As you can see, vaginal sex results in higher sperm temperatures, which increases the chance of pregnancy, which makes sense biologically speaking. So if you want to become pregnant, the best way to is to practice vaginal sex. Have a great rest of your day everyone!"