Probably aliens, or unusually advanced mutated humans, living normal lives among people in nineteenth or twentieth century America or Europe, could mold their body shapes to fit the prevailing fashions. They were always very human, but were always the most attractive humans because they could be as pointy-chested, flat-chested, broad-shouldered, as tall or short, as the most desired shapes of the time demanded.
Media: Almost certainly anthology of short stories, most likely paperback, possibly hardback from libraries. Magazines can’t be ruled out, but are less likely.
Published: By about 1980, probably well before. Could be 1970s; could be Golden Age.
Read: English, probably originally English rather than translated. Read before 1980. (Or not much later.) It "feels" like the work of a major well-known author.
Target audience: It was written like a standard short story for adults -- that is, not a “juvenile”. “Adult” audience means only not the YA/juvenile, not because of any X-rated “adult” themes.
Setting: City life in perhaps nineteenth century America or Europe. Although there may be a history of these aliens/unusual people adjusting to the cultures through the ages of the earth, the story comes to center on a time period when bustles were in fashion.
I had to look up this time period in fashion history: one of the various time periods in the story would be circa the 1870s.
I don’t remember whether the aliens/people could time-travel, or the story simply described how they fitted in to earth fashions over the ages.
The main plot was that aliens/people shape-shifting into human form could modify their bodies to fit the current fashions. It makes sense – you can have it and flaunt it! That is, they always appeared human, but they could be fatter, thinner, taller, strongman, make their waists tiny without needing girdles, women flat-chested to fit in and be attractive to human men in the 1920s, or actually pointy-chested in the 1950s, and so on.
I don’t remember if their motive for attracting human mates was a hostile takeover to conquer humans from within, or more simply the desire to live the best possible life on earth and blend in.
THE PLOT TWIST: An attractive alien/hyper-human woman was meeting a man intimately; perhaps just married after the customs, perhaps not. When she undressed, the man screamed and ran out.
She was shocked, extremely surprised and confused at his reaction, because had she not formed her body to be most attractive to the men of this period??
PUNCHLINE: She was unaware of the existence of --- the bustle.
Which were the last two words of the story, I think. A punchline ending in those last two words.
The reader is brought to realize that she shaped her body like a bustle. Being unaware that this would make her freakish suggests that it was uninformed aliens rather than just supernormal people.
I can’t pin what I remember of this down to a style. The subject seems Sheckleyesque, but I have been thrown off by hunting down the wrong authors for a story before.
I have used resources to search for every combination of words I could think of, and all I got was references to “hustle and bustle”.