Chibi Usa is Serena's daughter from the future. She came back in time to find the Silver Imperium Crystal so that she could take it back and save her mother in the future. She's very bossy and Serena doesn't like her too much at first, but she begins to love the little girl as they get to know each other better.

Chibi Usa becomes very good friends with Hotaru, Sailor Saturn. ^_^ They're so cute together, don'tcha think?

Chibi Usa's guardian cat (or kitten) is Diana, who is the daughter of Luna and Artimis.