Well if you want to get technical, the "sexy" cosplays are, in fact, cosplays. The accurate ones are just better. This one just happens to accomplish both of these things by being an accurate cosplay that just happens to be short, tight, and shiny.
What is /not/ cosplay is wearing fan items like some people who will wear a t-shirt from something and show cleavage. You have to have some intent to be the character, not just wearing something that shows you like the character :) even if the ironettes /weren't/ a thing, it'd be a cosplay.
If the first girl was cosplaying to be Iron Man, it would be crossplay, wouldn't it? Unless she is cosplaying as someone like 'Iron Woman,' if there is one.
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Jessica, you are doing it wrong. It doesn't make it anymore cosplay the more skin you show.