Crazy Rainbow Star
Please vote fairly! There wasnt a suitable item for the rainbow on her skirt excuse that please~
Sailor Cosmos was a character who played an important part in the Stars arc of the Sailor Moon manga, where she was revealed to be the true form of Chibi Chibi.
She may be the future self of the current Sailor Moon, reincarnation or descendant. Naoko Takeuchi herself seemed to imply when questioned that Cosmos' true identity was intended to be ambiguous to everyone, including herself.