|Occupation:||Guardian of the Cosmos Crystal|
|First Anime Appearance:||N/A|
|First Manga Appearance:||Act 52 Stars 10|
|First PGSM Appearance:||N/A|
|English Name:||Guardian Cosmos|
Guardian Cosmos was the guardian of the Cosmos Crystal in the Galaxy Cauldron in the manga. Usagi encountered Guardian Cosmos after she threw herself into the Galaxy Cauldron in Act 52. She appeared to be quite small, only a few inches tall, and wore a sheer, beaded dress. She also carried a glowing staff.
After remarking on the brilliance and purity of Sailor Moon's Sailor Crystal, Guardian Cosmos made several ambiguous statements about how a Sailor Crystal much like Sailor Moon's had been born from her and was cast off, seeking to create a new history for the stars and then return when it was finished. Guardian Cosmos then inquired whether Sailor Moon wished to start a new life as a new star, or to resume her old life just as she was. Usagi and her friends elected to remain as they were, and the Guardian sent them all back to Earth.
As the Senshi left the Cauldron, however, Sailor Moon asked about Chaos, and Guardian Cosmos stated that Guardian Chaos and the Chaos Seed had reintegrated into the sea of the Cauldron, meaning that one day they could be born again.