Keep going

You are shocked at what you just did but you're overcome by a feeling of dominance. You try to push it out of your mind as you continue down the mysterious hallway. Now you are certain that something is wrong with you. Its simply impossible to come that hard and long, especially twice within an hour. You decide to take a closer look at your genitals. Your cock seems normal and you lift it up to get a closer look at your balls. They seem much larger and firmer than they were before. How did this happen? Did someone do this to you? You begin to run as these thoughts start to overwhelm you. You keep running and running down this seemingly endless hallway until it finally does end...

You slow down as the corridor leads into a large room.

"Hello?!" you ask.

"Is anyone here?!" you shout one last time.

Suddenly a voice erupts out of nowhere.

"Hello Marck. We have been awaiting your arrival." the ominous voice proclaims.

You scan the room for a possible source of the voice but you find nothing, the room is empty.

"Who are you?! What is this place?!" you shout.

"I cannot tell you who we are yet, but your questions will soon be answered. Have you enjoyed the improvements we have done to your body?

"What? What improvements?" you ask, already fearing the answer.

"Our little upgrade of your genitalia. Your old ones wouldn't do for our purposes, we had to exchange them for something better."

"You did this?! What did you do to me?!"

"You should thank us. We have given you the ability to produce and ejaculate great amounts of semen. We also genetically modified your spermatozoa. They are now more resilient and capable of surviving for weeks within the female uterus, making them far more fertile than those of any other organism. Every female you inseminate will inevitably become pregnant."

"Pregnant?!" you ask in shock. Your mind begins to shut down as it tries to make sense of this nightmare. Then you remember Alex. "Holy shit, I impregnated my best friends girlfriend!".