Did some amateur theatre while in the last year of high school, one play was in a historical setting (around 18. century), and the women wore costumes from that period.
That involved dresses with corsets, and they were a hassle to get into. We didn’t have a proper wardrobe, just a general backstage area where I tended to hang around for obvious reasons.
The female lead was 18, cute as a button although a little stuck up, tiny girl with tiny tits. She needed help getting into her dress and there would often be some slippage during that process. The other female cast members helped her while I somewhat creepily stole glances until my girlfriend at the time who was also part of the theatre group (but not part of this production) caught me looking and told me to knock it off.
It wasn’t blatant enough to garner any serious reaction though so I sort of got away with it. Got a good look a couple of times though…
Later, as a university student, we used to put up an annual review, the type with a series of skits and songs, mostly humorous. The only area for changing costumes was a cramped space next to the stage, as we held it in the student bar. So whenever you were waiting to get on you stayed there, and those who came to change had to deal with whoever was down there, no room for privacy.
At least two female cast members had no particular inhibitions and just stripped down to their panties (no bras) whenever they had to change. Saw both girls’ breasts full on as I didn’t even have anywhere else to look.
That was nice