Hormones

The initial effects of the semen substitute had worn off, but now you began to feel tingling in your lower abdomen and especially in your crotch. As you looked down you saw your nipples were hard and erect, and you barely noticed your breathing had changed to panting. Meanwhile, your thoughts were becoming overwhelmed with the driving need to fuck something.

The only creatures nearby were the Grey doctor and his medical staff, and none of them had genitalia. As you scanned the room, you saw a set of probes hanging from the ceiling, but they were out of reach. "Doc, I..." you gasped. "I really need to fuck something! Right now! Fuck me with a probe!"

The Grey doctor gave you a strange look, then waved his hand to direct a colorful series of scanning beams at you. "This is very interesting," he said. "Instead of fully breaking down and removing the most recent byproduct from your internal power supply, your hybrid physiology is converting it into something similar to the Cuni hormone for sex drive. What you're experiencing now is similar to a what a Cuni feels near the height of their mating cycle."

"Don't explain it!" you shouted. "Just give me that damn probe and fuck me! Now!"

"Unfortunately, these types of medical probes are not designed for that. There is too much risk that the probe would be damaged by the **** physical stress, and it might injure you as well."

"I'm not a Cuni!" you protested. Then, you jumped up on the table and started reaching for the largest probe you could see. Suddenly, a wave of greenish light struck, and you couldn't move. Soon you felt yourself being lowered onto the table and then straps emerged locking your neck, waist, wrists and ankles to the surface. Once the restraints were secure, the green light vanished. You struggled to move, but the straps held you firm. "Damn it! Don't leave me like this. I need to fuck something. Anything!"

Turning your head you saw the doctor standing next to the other Grey medical staff, and from what you could deduce they were likely having some kind of telepathic conversation. Finally, the doctor turned and approached. "You may not be a Cuni, but your reproductive organs and surrounding anatomy are. It has been many years since we've had to deal with a Cuni during their mating cycle since they are usually sterilized. There are specialized probes designed for use on Cunis in this state, but there are some risks."

"What kind of risks?" you asked.

"The intensity of the stimulation it generates might overwhelm your nervous system," explained the Grey doctor. "Also, you might become addicted to using these probes and unable to achieve an orgasm without them."