Collaborative sex stories let us write the plot together

(Her Secret Fantasy, continued by Wifes-out...)

You look over to your girlfriend, who is sitting at a desk trying to turn the goblet in front of her into something only to have it change half way and then stop and become a goblet again.

“You know who could do that?” you ask her, levelling your wand.

“Hermione!” she blurts with a mischievous grin.

With a quick elaborate wave, Rachel begins to be assaulted by a magical wind swirling around her. As it gains strength her features begin to twist and contort into the spell. As quickly as it began it subsides, leaving her sitting there in a new skin.

Rachel is now the spitting image of Hermione, right down to her Gryffindor house robes. She is running her hands across her face and down her body, feeling the change.

“Do I look different?” She stutters as she hears her voice as someone else’s.

For the first time she sees the outline of your magically enlarged penis. “There’s no way you’re fucking me with that!”

You put a foot up on a chair, making sure your giant cock is on display. “Maybe there is something else you would like to change about your new self?”