Ive said this before.
When the breasts are free flowing, they show.
The pointed shape and swinging, bobling will show off to the world they are there.
The pointed aspect of nipples alone is what will give it off.
When wearing a bra, they round off and are shaped.
The thing that happens here is similar tot he effect that the daytime running lights originally had.
At first you notice, but then over time its normalized and people no longer notice.
Same with the breasts. Peple are sue to the round offed shape of a bra and unless really large, pay little if any attention.
When they are sharp and pointy, they show instantly.
Erotic wise, I have very little experiance, my other half refuses to touch them.