He is a conundrum, and just as the Black Rose Saga seemed to have nothing to do with the rest of the story, Mikage is literally forgotton after he plays his part in the series. He appears only in the Black Rose Saga, and is never mentioned again. At least, not that I remember. Anyway, Mikage was the leader of a research project a long time ago at Ohtori Academy, so far back that there wasn't a Student Council and therefore no records. He was in love with a woman named Tokiko Chida, and also had a strong bond with her ailing brother, Mamiya. He hoped, by the research he was conducting, that he could gain eternity for Mamiya, who was undeniably dying. Akio took advantage of Mikage's genius and it was he who gave Mikage the idea of gaining eternity. I really can't be sure about any of this, because I need to watch the Black Rose Saga over and see if I can figure out the nuances, but as far as I can tell, Mamiya died a long time before the show takes place, and Akio used a younger version of himself to keep Mikage thinking that Mamiya was still alive. Between Mikage's strong feelings for the boy and Akio's manipulation, Mikage stayed in that one reality and never grew older. His goal, after Utena showed up, was to defeat her, kill Anthy, and replace the Rose Bride with Mamiya. He thought that this would "gain eternity" for the boy, and so save his life. Mamiya (or at least the manifestation of Mamiya) cultivated black roses deep under Nemuro Memorial Hall, where Mikage had done his research years before. Appearantly, the hall had burnt down (Mamiya was suspected of starting the fire, although it has been hinted otherwise) and one hundred boys were killed. Anyway, any distraught students seemed to be drawn to this place to talk about their troubles. They would go into an elevator, where they would talk into a small window. After they had bared their souls, Mikage would say to them, "I see. You have no choice but to bring the world revolution. The way has been prepared for you." The first Black Rose Duelist was Kanae Ohtori, who came to see him because of her relationship with Akio and how she couldn't get along with Anthy. Mikage led her into a room, much like a catacomb, where coffins lined the walls. He pulled one out and gave her black ring, which he told her he took from a dead duelist. Appearantly, the duelists' white rings turn black when they die. Then Mamiya came from behind and stabbed Kanae with a black rose. Mikage obviously does this to all of the innocents that he turns into Black Rose Duelists. When they duel, there are rows of desks in the arena, and the duelists fight around them. There are also red outlines of bodies all over the ground. On each desk is an item that is specific to whichever Black Rose duelist is fighting Utena at the time. When the duel is over, all of the desks slide together at the center of the arena. This power he gives them allows them to draw a sword from the chest of whichever duelist they are closest to. I don't recall if it showed who Kanae drew a sword from, though... anyway, Mikage orchestrated all of the Black Rose Duelists' fights with Utena. Later on, she found out that it had been Mikage who turned all her friends against her, and in usual Utena fasion, she almost kicked his butt. If she hadn't seen the white rose signet on his hand, she probably would have... After that, Mikage dueled Utena, but his delusion was clear  he always addressed Utena as "Tokiko". He lost (big surprise) and afterwards, Akio told him that the Mamiya he had known had died a long time ago and the one he had been living with never really existed. He also told him that he could graduate now, after all these years. Then he said something very cryptic (not that that's a surprise either)... something to the effect that Mikage had never existed either. (What's up with that?!)