[cufan86]

But I think this fits. I posted this a few years ago but have added a couple of details.

A former girlfriend of mine was in drama at a university in the 1980s when we were dating. I never got to see it this particular play, but she told me about how the actors didn't have time to go to the dressing rooms during the show and would change backstage. She had a dancer's body with cute little A cup titties. Most plays, she did not wear a bra as some costumes would not allow it and it took extra time to take it off and put it back on.

She didn't consider it a big deal as she said it was mostly girls and gay guys. There were a few straight guys but they mostly kept their eyes to themselves or at least were not overtly ogling the girls. She said it didn’t really bother her as long as they weren’t obviously staring.
(My guess is the boys were smart enough to take quick glances)

She said she was only embarrassed one time. They were doing a dress rehearsal and some local high school kids and their drama teachers from a few of the local high schools had come to watch. They started out in the audience. However, as the play progressed, apparently about a dozen of the students were taken around back stage with a teacher to look at the technical aspect of it. As such, the actors started going behind a screen to change. My girlfriend, a bit ditzy at best, didn't clue in and when she came off stage she pulled her costume over her head, so she was only wearing a pair of white panties. As she went to get her next costume, she realized that she had an audience of several high school boys. She said she blushed but thought it would be worse to run off so she proceeded to finish changing. She said the students got about a clear 15 second view of her tits from about 10-15 feet away.

She and I have remained friends although she lives far away and we rarely see each other. A couple of years ago we were reminiscing about our college days. I brought this incident up. She admitted that she was embarrassed at the time but later got turned on thinking about it. I asked her if anything like that happened since. Unfortunately nothing had. Or nothing she would admit to.