There is no verbal or physical contact just the sense that at some point they know that she knows and that she continues to glance while acting as if nothing is unusual.
Her first experiences was waiting at a quiet bus stop and a old guy would sit at the stop on the other side of the road and jerk through his pants pockets staring at her. She found she didn't mind it and he would show up 2-3 times a month and she would watch. After a time he sometimes got his cock out and she enjoyed it, not staring at him directly but on the side in a way that he knew. One time she came across him in a park while jogging and there was a silent agreement, she sat on a nearby bench pretending to fiddle with her shoes while he had a wank and a flash on a bench next to her.
After moving cities she found other similar types (that respect personal space) and she grew a bit bolder about it. Now it's now part of our relationship and we visit certain public spots where she can do her thing while I wait nearby. She has a very good eye for the "right types" so sometimes it can happen while we are on travels/vacation. it gets her proper horny and I am fine with that
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