Not exactly sheer....
 

1979!

I was 17. The guy who’d taught me to play guitar was taking me to see Status Quo in Sheffield (back when they were a rock band!) and what I didn’t know back then was that it was pretty much de rigeur to get their early and dive into a suitable drinking establishment to get adequately oiled before the gig!

Never mind the drinking! One barmaid in particular was not only spectacularly gorgeous but was very obviously braless under her cheesecloth shirt. I was transfixed by her lovely tits and nipples the entire time we were in there!!

The first of many
 

I was at the U and a friend of mine came to my rooming house in a tizzy. He told me that Amy, a gal I slightly knew as she dated a guy I knew, was at the student union with a see-thru blouse on. He is about slobbering over himself as he related it to me.

So I headed down to the SU a couple blocks away. Sure enough Amy was there with her ample boobs on display under a very sheer blouse. She was surrounded by a small crowd of guys including her bf. I made some comment to her and we laughed about it.

I walked back to my room and caught my friend jacking off in my bathroom. He just said he couldn't help - had to do it. I resisted the temptation to do it also. I ended up seeing her boobs a few other times when I visited my friend who dated her and she would walk around his place topless or nude frequently.

The first incident got me hooked on see-thru women's clothing and I have been a big fan ever since.

I'm a 70's kid so there were too many women going around braless at that time for me to remember whom I saw first. But the one was that struck me the most was Jacqueline Bisset in "The Deep." Who could forget that scene?!

Wonderful...
 

Oh yes, so horny! If I think 25, 30 years back, 50 % of girls and womem did nit wear bras... And some no slips, too! What a hot time! My wife doesn't wear bras until today, and at holiday no slips, too!

sl*t Girl
 

I went to a party dressed in a see through blouse. I let my hubby take a picture of me in it.You can clearly see my nipples. When I took my coat off I had most of the guys hanging around me. I wound up giving several blow jobs and getting fucked by 2 different men that night. My husband got to watch some but he got nothing because I keep his tiny dick locked in a chastity cage. I did let him lick my pussy clean each time though.

Not a shirt, but I had stayed at a friends place & in the morning, his mother came out of her room to grab something & was wearing a tight knitted sweater & clearly no bra. We could clearly see her boobs. I looked at my friend after she went back into her room & he just shrugged his shoulders & we kept watching TV.

When she was young, my first partner had an exhibitionist streak. We were students in London in the seventies. Often, she'd wear thin translucent blouses with jeans or a wrap around long skirt.

Occasionally for a party, she go braless under a perfectly transparent blouse. She never discussed it with me or asked if I minded her showing off tits in public.

It wasn't kind of thing you saw very often. She was very thin with firm boobs, so she could carry it off in a way that a bigger woman couldn't have done.

It was particularly impressive when her nipples got errect. Perhaps that happened because she got aroused by people looking at her tits. Maybe, it was just the cold air.

Our friends were far too cool to comment, although I did once hear a couple of oiks talking about her in a way I took to be disrespectful. I remember thinking "take a good look guys cos you're never going to have a woman that confident and beautuful."

Looking back now, I could have have a lot more fun with her if I'd had a little more experience of life.

I was 13, a similar aged girl wore a tranparent blouse without bra. She was surrounded by a bunch of guys. Not in the US, btw.😁
Like this TV screenshot:
https://i.ytimg.com/vi/8hBij7VWr60/hqdefault.jpg

We could use the return of that fashion trend at any time…. I Loved those days - when you saw women braless and teasingly transparent blouses regularly. 70s freedom…

Back in the late 70's early 80s I used to have a little hustle setting up Aquariums. I would help decide on dimensions, fresh or salt, background and landscaping, and aquatic life (plants and fish).
My of the Mothers that I was working for was wearing a green pastel tanktop without bra. What we would call a MILF today. When showing her how to set up the different filter systems the shirt did get a bit damp turning from slightly see-through to outright translucent. She had several of these shirts in different colors.
Very memorable.