Neo Queen Serenity
During the second major story arc, it is revealed that Usagi, as Serenity, will eventually become the queen regnant of a new Silver Millennium called Crystal Tokyo, which will already exist in the 30th century. She is first seen in this future form in Act 16 of the manga and Episode 68 of the anime. Usagi learns that she will be given the title "Sovereign of Earth," and Mamoru will become King Endymion alongside her. It is stated in the anime that she becomes Neo-Queen Serenity after warding off a second Ice Age, though the specifics of this are never discussed.
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