This show offers us a plethora of symbols and archetypes that can get downright      overwhelming. Let's try to parse them out a bit.
Fairy Tales
One of the most consistent sets of archetypes, of course, are the Prince and      Princess, which are title, costume and subject position in one. Utena meets      a Prince and decides to be one herself; she seeks to be a Prince for Anthy,      to protect and rescue her. Anthy plays the part of a Princess, flouncy dress      and tiara and all, being fought over in duels. Akio encourages Utena to      develop as a Prince, only to switch her to Princess so that he can render      her passive and steal her active power, thus making it doubly clear to us      exactly what positions are encoded by the distinct costumes of Prince and      Princess we see Utena moving between. Another variable is added, however,      when Akio tells us that Anthy is actually a Witch--the sister of a Prince,      the one woman who can never be a Princess.
That, of course, suggests that the relationship of Prince and Princess comes      packaged with romance and sexual connection, which is, theoretically, a      different mode of relation that the familial one between siblings. And certainly      the sibling pairs of this story, all of whom do seem to contain romance,      usually in the form of the sister desiring her brother, are deeply troubled.      Nanami and Kozue both want things that they only feel free to seek in very      roundabout forms, becoming extremely possessive of their brothers but not      quite daring to make direct romantic overtures. This suggests that they      themselves consider their desire dangerous or wrong in some way.
Princes' sisters, then, cannot be Princesses, and thus do not have a place,      do not have a role in the closed Prince-Princess set. They are not contained,      and their desire for the Prince is not proper, as a Princess's would be,      but a dangerous disruption of order. Note that desire, in and of itself,      is not wrong in this system. The sister's desire itself is in no way different      than that of a proper Princess; rather it is made wrong purely by circumstance,      and by no fault of the sister. (Note also that all this works on the metaphorical      rather than the literal level. Literally, a sister could be a princess for      some other prince, who is not her brother. Metaphorically, there is only      one Prince, one Princess and one sister, subject positions that any number      of actual people may occupy. The sister is any woman who is outside the      accepted economy of gender roles and relations.)
The fact that the sister's desire is coded as wrong, however,  does not make      it go away, and that reservoir of want remains. Denied a valid outlet, it      turns into other things. In Kozue, ambition, a desire to possess power.      In Nanami, passion directed at her brother in any form he will accept, and      hatred directed at any woman who comes near him. Fortunately for Nanami,      she evolves over time and escapes the sister/Witch's fate somewhat.
Anthy is the one who takes the final step and possesses her brother, never      mind that it's forbidden. This turns her into a Princess, but, because she      is still a sister, she takes on an incredible load of guilt (those swords,      the anger of others) for having done so. Her Princess-ness winds up tainted      by her transgression as a Witch and her Prince turns from good to evil,      while her free, unassigned power as a sister/Witch is bound by her aspect      as a Princess. And there our story opens.
Knowledge of Good and Evil
This arrangement also has a layer of fairly explicitly Christian imagery.      Akio calls himself the Morning Star, which is one of the various poetically      derived names for Lucifer/Satan/the Devil. Since he is the evil/destructive      part of Dios, he certainly qualifies as a fallen angel.
The tastiest part of this, for me, is that Saito might have really known      her references. The Morning Star is a name for Lucifer because Lucifer,      before falling, was the herald or forerunner of Christ (the rising sun).      In this formulation, Utena is the most logical candidate for the role of      Christ, and, indeed, she does sacrifice herself for Anthy, and possibly      for Anthy's sin. As noted on the Agency and Choice page,      though, that sacrifice is not what actually frees Anthy. Instead it is part      and parcel of the Prince, which is as much of a trap as the Princess. Anything      that comes only in opposing pairs, in this story, is a false lure.
Ages of the World
The emphasis on dualisms has a counterweight, however. Some themes from Hindu      cosmology
1 run through this story as well,      emphasizing an imbalance and an empty third space in the narrative. Interestingly,      Nanami is a primary carrier for the symbols that point in this direction.      Her episode with the egg, which reflects Dios' egg-prison and the egg the      duelists speak of breaking, her transformation into a cow, her persistent      case of elephants during her trip to find the curry powder, all of them      draw from the Hindu symbol set. In conjunction with the character design      of Dios and Akio and Anthy, dark with bindi on their foreheads, this suggests      yet another way of looking at the character archetypes.
We can look at Dios and Akio as aspects of the Trimurti, only missing their      third, which seems to be a major plot point. The power to revolutionize,      to turn that is, harks strongly to the whole concept of yugas, the wheel      of ages each turn of which ends with the destruction of the world preparatory      to the creation of another. Of course, if this is the cosmology Saitou is      calling on, she has altered and recombined it in ways not covered by any      current interpretation, but that is not at all uncommon in anime and manga.       The aspects of the Trimurti are not usually associated with any of the      four yugas, though Vishnu, in another aspect, is. In the world of 
Utena,      however, these aspects do set a strong stamp on the different ages we see,      depending on who is free to move and act in each one.
I take Dios as the Preserver (Vishnu) and Akio as the Destroyer (Shiva).      Dios is the one who preserves a stable condition (for all girls to be princesses,      to be protected from all trouble). Akio, the End of the World... well, what      more do we really need to say? The Preserver's age ended when his sister      sealed him away to save his life, sacrificing and suspending her own life      by doing so. The Destroyer's age ends when Utena makes it through the gate      and offers a new choice to Anthy. What is behind the Rose Gate, I would      say, is the aspect of the Creator (Brahma)--the possibility of a new world.
This set of archetypes also marches well, iconographically at least, with      the sexual theme of the story.  As the story progressed      I started out thinking of the sexuality as radiating from Akio, who, after      all, appears to be sleeping with his fiancee, his fiancee's mother, his      sister, 
and Utena, not to mention Touga and every duelist who confronts      Utena, but eventually I saw all of it as ultimately coming from Anthy. That,      I think, is the witch aspect, what Kozue calls impure, the opposite of a      proper princess. It's filtered through the age of the Destroyer, though,      which is what I think makes it such a tangled thing, always doubled back      on itself, claustrophobic, hurtful. The three sibling pairs, Juri and Shiori,      definitely Saionji and Anthy, Saionji and Touga, Kagami and Mamiya, they      all have relationships of desire that result in pain and death and stasis.      This is a fairly classic way for Hindu philosophies to interpret lust, one      of the hallmarks of the Kali Yuga, the last age before destruction. There      is also that rather disturbing shot of Anthy riding in the car with Akio,      when her responses look and sound like sexual pleasure, and then Akio asks      if she's in pain and we see a flash of the swords. Sex and pain are completely      elided at that point, and it made me wonder if they weren't elided all along.      Again, we see how tangled everything becomes around a witch-who-is-a-princess.
We also see the very unfortunate ways in which the Preserver and the Destroyer      are elided. Stability and death, in this story, are the same thing. Preservation      does not nurture, and destruction does not clear the way for anything, as      they should do.  Rather, in the ultimate oneness of Dios and Akio, we see      preservation that smothers and destruction that feeds on itself and never      ends.
Anthy herself  represents, I think, not so much power or even a particular      archetype as a chance, an opportunity to turn the ages. She is the occasion      of agency, but doesn't have any of her own except at the very beginning,      when she chooses to end the Preserver's age and take on the hatred that      action engenders, and at the very end, when she reaches out to Utena, making      a new choice and ending the Destroyer's age also.
1. It is worth pointing out that "Hindu" is a catch-all phrase that      can encompass a vast array of Gods, legends and philosophies, some of them      very contradictory, just as "Christian" encompasses both Catholic      and Pentecostal, despite significant differences in philosophy and practice.      Anyone interested in more detail on the gods and concepts noted here would      do well to read the work of scholars who deal with a specific aspect      rather than trusting any source that attempts to lump them all into one.