The third holiday Transformed book I wrote was Transformed for Valentine's Day. I mean it seemed kind of obvious to me. Maybe not obvious to you, but when you've written a shit-ton of these you start to get the hang of it.
The thing with writing a gender swap story is you always need a method. Mostly I use witches, potions, or experimental drugs. Since this was taking place on Valentine's Day it seemed pretty obvious to me: Cupid's arrow goes astray and turns a guy into a woman.
In this case the arrow turns him into a double of the girl he's secretly had a crush on. So for Valentine's Day he's the girl of his dreams. He ends up hooking up with one guy and then another guy and then he runs into the girl again. Some mayhem ensues then!
Valentine's Day is over, but you can still buy this for $2.99 on Amazon!