The Book of Spells
Story by wazza
Another one of my favorites from Overflowingbra (also can be found on fictionmania). The story centers around a boy and a girl with a magical tome :p. There are a few strange transformations, as well as some mtf transgender stuff. I couldn't find the story here so I decided to post it. Enjoy!
Edit:
Actually, here is the zip file from overflowingbra. A copy-paste of this story doesn't do it justice.