What you need to preserve in mind approximately cosplay is that the source fabric mainly comes from comic books and movies. And the illustration of girls in that supply material hasn't usually been realistic or body-tremendous.

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Despite difficult work from authors and creators like Kelly Sue DeConnick who are pushing for changes in the depiction of women characters, in comics the ones girls characters have a tendency to be scantily clad. They command unrealistic body proportions, and they are often depicted in openly sexual poses.