The backpack pulls off her whole skirt

Anna felt the clasp on the back of her belt slowly pull open under the pressure of the backpack’s pull. She desperately tried to reposition her body to decrease the force of the pull, but to no avail. Suddenly, the clasp snapped entirely. With horror, Anna watched helplessly as her skirt was completely whisked off her body. She watched it dangling from the backpack in front of her, swinging back and forth, taunting her. She tried to grab the fabric, but the guy suddenly slipped ahead through the crowd.

She kept walking forward, because what else could she do, but now she was keenly aware of the nudity on her bottom half. There was nothing at all covering her fully exposed butt, and the untucked front part of her shirt was too short to hide her soft pubic mound and everything below it.

She watched as the backpack, and her skirt, grew further and further away. Running through the crowd to catch him greatly increased the chance that someone would see her in this condition, but could she really afford to lose her skirt, maybe permanently?