Below, you can see a small screenshot of Mikage and Mamiya in the last episode of the Black Rose Saga, Qualifications of a Duelist (episode 23). This is just before Mikage went to duel Utena.
And here you can see Edouard Manet's painting, "Olympia":
This painting was rather a sensation at the time of its release, because, while painters were accustomed to use prostitutes as models for their nude paintings, Manet painted his subject as a prostitute, rather than as a dreamy nude woman. It was, apparently, just plain scandalous.
Note that while the poses are slightly different, the bed and background and general positioning is very similar. So one might draw the conclusion that Mikage was being portrayed as a prostitute himself.
Many thanks to Bara no hitomi for noticing this and telling me about it, as well as finding the photo of the painting for me online) and giving me a bit of background on the Academy's reaction to the painting.
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