Brainbox

As she lay strapped to the bed, she had no idea what was going to happen, then she saw the scientist strap himself onto a bed next to hers. Suddenly she found herself in that bed, but as she looked around realised that she had swapped places, and now the scientist was in her body, and she was in his.

The machine had swapped their brains around, at first she panicked, but then she realised that she could have a lot of fun here. If his body, with her brain, was released, she could fuck her own brains out, if her body was released first, with the scientist's brain, he could go and experience the world through the eyes, and other orifices, of a woman.