It was like a scene out of a b-grade science fiction movie from the 50's. The saucers came from the heavens above in their multitudes, hundreds upon hundreds of eerie green and silver disks invading our humble planet's very atmosphere. Our primitive technology no match for either their indestructible hulls, or even their sophisticated cloaking technology. In fact, we never realized their presence until it was too late and they had assimilated half the planet into their folds.
The saucers, if you dare to believe it, were actually about as small as literal saucers. This fact along with their impressive cloaking technology made them absolutely undetectable to our inferior radar sensors. They scattered across the globe in small groups, traveling to major cities and small towns to hide in the trees and bushes and in the shadows of alleyways. The saucers waited patiently from these hiding places, waiting for the most opportune moment to attack. Waiting at first for isolated targets they could pick off one by one. For once they secured a perfect mark, the body snatching began.
The moment you were targeted, one of the saucers would leap into action. From a port in the bottom of the tiny craft a fleshy, tentacled worm creature would emerge and force its way into your brain through your ears. Once it's latched its tendrils to your gray matter, it would forcefully blast your brain with bioelectric impulses, devouring and digesting your memories so that it could take over the reins from there. Your very consciousness would then be extracted from your body in the form of a translucent colored silicone dildo, pulled from your rear-end like plucking a carrot from the soil. The alien body invader would now be in full control of your body, and would begin the step of reshaping it to its perverted liking.
The brain worm will fire more impulses through your nervous system to various hormone glands across your body. These impulses would force your body to produce a volatile chemical cocktail of hormones that would transform your body in a mere matter of moments. Invariably, it will force your body to transform into a woman of some kind, usually a woman who happens to be a hermaphrodite. From there the transformation the body snatcher will force its new puppet to take will vary. It might make your body walk on all fours. It might make you grow five more rows of breasts. It might make your anus large enough to fit a Greyhound bus. It might make your face stretch out into an absurdly long dick-sucking tube. No matter what the change it makes, there is no doubt that they will be undeniably salacious.
Your consciousness, trapped inside its phallic silicone prison, will be transported to the Mothership and placed into cold-storage with several more dildos. Occasionally you'll be brought back down to Earth to be used to pleasure another victim of the erotic body snatchers, forced to suffer the humiliation of being a self-aware sex toy. As for your own body, the brain worm will seek out more marks for its brethren to invade and transform, and transform the Earth into the galaxy's greatest orgy.