Usagi: Guardian
This is Luna, Usagi's motivational cat. They become very good friends battling evil together. In the manga, she becomes human three times.
Usagi first met Luna when she was running to school (she was late, as usual). She tripped over Luna, who was walking along the sidewalk. Usagi picked up the cat sympathetically, apologizing for any harm. She realized the bandage on Luna's forehead and took it off. Usagi saw the cat had "a crescent bald spot" where the bandage had been. The cat escapes Usagi's grasp, and saunters away. Eventually, Luna becomes part of the family. Usagi soon finds Luna can talk; the bandage had stifled her special ability. Once Luna had convinced Usagi that she wasn't dreaming, she explained that Usagi was Sailor Moon, champion of love and justice.
Luna turns human at the end of the second series. Unintentionally, she meets a man whose name she learns is Kakeru. Luna begins to have feelings for him and visits daily. Sailor Moon is confronting the enemy that has appeared when Luna comes to terms with the fact that Kakeru would never love a cat. After the battle, Sailor Moon is filled with sympathy for Luna and uses her power to turn her into a human for one night. Kakeru explains he already has a love, at which point Luna realizes she does, too.
The second time was in the SuperS series, in the final battle between Sailor Moon and Nehelania. The Senshi become their Eternal form while Luna, Artemis and Diana turn into humans to help Sailor Moon defeat the enemy.
The final time is during the StarS series, when Tin Nyanko appears. She is able to turn Luna and Artemis into their human selves. They flee from her after being confronted, without much success. Tin Nyanko catches up and attacks them, taking their ability to talk.
Luna is a very serious cat. She nags Usagi about many things, but not to be annoying. She's a useful companion and cheers Usagi up when she's down. She feels responsible for Usagi.
