Luna is a beautiful dark black cat who appears throughout the entire series.

In Sailor Moon, Luna discovered that Serena was Sailor Moon, and gave her a locket that she could use to transform. In Episode 2, she gave her the disguise pen. In Episode 5, she was told by Central Control that Amy might be from the Negaverse, but later discovered her to be Sailor Mercury, and gave her a transformation pen. In Episode 7, she discovered that Raye was Sailor Mars and gave her a transformation pen. She also gave a transformation pen to Lita in Episode 21 after finding out that she was Sailor Jupiter.

In Episode 39, it is shown that Luna and Artemis were sent into the future by Queen Serenity to awaken the Sailor Scouts if the time should come. After the flashback, Luna was nearly killed by Malachite, along with Artemis, but they survived, and ultimately, Sailor Moon finally killed Malachite.

After Queen Beryl was destroyed, the Sailor Scouts lost their memories of being Sailor Scouts, but in Episode 1 of Sailor Moon R, the threat of Alan and Ann forced Luna to restore Serena's memories, and, in Episode 2, those of Amy, Raye, Lita, and Mina.

In Sailor Moon Super S, it is revealed that in the future, Luna and Artemis will get married and have a kitten named Diana, who travels into the past as Rini's companion.

Whenever Luna sees anything that resembles her (such as a clock cursed by Ramwoir, and Rini's Luna Sphere), she denies that it does. In Episode 3, she draws a picture of Serena while she's fat. It's shown that Luna Ball doesn't get along with her. In Serena Times Two , while Rini is attacking Serena, Luna is knocked out of the way by Luna Ball. In A Curried Favor,when Sammy is trying to cheer Rini up,everyone is completley clueless and unaware that Luna Ball is attacking Luna.

Voiced by Jill Frappier