Her panties

Her wand released a few sparks and Ginny expect to see the quill lift, but instead she felt her cotton panties quickly sliding down her legs, passing through her feet and ending up behind the student in front of her.

"What the h..." she thought that she had felt that. But it could not be right. She touched her skirt to see how she felt beneath…

"SHIT!" she thought, quickly snapping her legs together and trying not to freak out!

"HOW DID THAT HAPPEN?! I HAVE TO FIX THIS WAND! I AM GOING COMMANDO IN THE CLASSRROOM! I JUST LOST MY PANTIES! MY PANTIES GOT THROWN AWAY FROM ME!" she thought very embarrassed. "WAIT! Where are my panties?!" She quickly looked underneath her table and saw where her undergarments were.