As a girl it`s not always easy to simply pull it out and rip a piss. That is why women tend to pee themselves more often, I did and still do at least. It is not a secret on how to sneak a panty piss and no one notice, simply keep your legs together so they stream the pee to your feet and let go a little at a time. Works with dark pantyhose too, by the time you finished they are already dry looking. I also keep a spare panty and pantyhose in my bag, just in case.
http://www.realwetting.com/sneaky-swimsuit-pee.html
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