Now that Professor Tomoe and Kaorinite have been destroyed, it is up to the eight Sailor Guardians to confront Mistress 9 directly and eradicate her once and for all. As Pharaoh 90's complete vesselization looms nearer, Hotaru's consciousness is determined to do whatever she possibly can to save Chibiusa and stop Mistress 9 from using her body for evil ends.
Now that a new and mysterious monster has appeared, the Sailor Guardians are bent on finding out by infiltrating Mugen Academy. While battling another of these new monsters called Diamon, Sailor Moon and Sailor Chibi Moon befriend a strange girl with unusual powers. But just what kind of connection does she have with the new enemy?
A few months after the defeat of Death Phantom and the Malefic Black Crystal, Usagi, Ami, Rei, Makoto, Minako and Chibiusa are all enjoying their normal lives. However, new enemies appear out of nowhere and are attacking humans in order to absorb the hoste or souls of their human victims in order to live and sustain themselves on Earth. Can the six Sailor Guardians stop this new, unidentified threat?