She wait for a while

Sophia did not feel like having to be out there without a shred of cover. She was effectively trapped until an opportunity suddenly presented itself. One of the girls had entered the stall next to her and put down her stuff. Sophia overheard her speak to her friends:

"I'm quickly gonna go to the toilets, don't leave without me!"

The girl exited her stall and walked away, leaving her things unattended. Sofia could see her towel hang from the little bench, almost touching the wet floor. It was bright red, with some sort of logo on it. Sofia could only see a small corner of it from within her stall, so she could not make out what it said.

Taking the towel was tempting. She could wrap herself up and safely get out of here. Everybody else was probably in their own stall right now, but they would not be for very long. Whatever move she was about to make, she would have to do it quickly.