You thought aliens were just made up, that they didn't really exist, that they didn't kidnap people to experiment on or whatever.
It turns out you were wrong.
In the middle of the night, you open your eyes and are blinded by green glowing lights. Through your blurry vision you see the faint outline of a spaceship, and before you know what's happening you're being pulled out of your bed by the light, all control of yourself relinquished to some strange force.
Your consciousness is faint. You scarcely see the aliens themselves, only feel things inside the ship. You seem to be in a sort of laboratory, one which smells strongly of pleasant pheromones. It puts you beyond caring to notice that much- incomprehensible chatter and bright white lights are all you sense. Other than your nudity. That's something you notice. You can feel your crotch stir, wanting to be touched, but you're bound down, unable to move your arms or legs.
Soon, you feel a needle jab into your head, but no pain or bleeding- it's more like being poked. In a further stir of euphoria, you lose consciousness again. When you come to, your situation will be even stranger.