Princess Usagi Small Lady Serenity, formally known as Chibiusa, is the crown princess of Crystal Tokyo and daughter of Neo-Queen Serenity and King Endymion. She travels from the 30th century to the 20th century seeking aid from the Sailor Guardians. Her nickname combines "chibi," meaning small person, and "Usa," short for Usagi, to distinguish her from Usagi Tsukino. Chibiusa possesses bright pink hair styled in cone-shaped odangos that resemble rabbit ears, and red eyes. Chronologically over 900 years old, her physical growth halted around age five due to not awakening as a Sailor Guardian, a condition linked to the Silver Crystal’s power and her emotional immaturity. Feeling lonely and doubting her mother’s affection, she shares a close bond with Sailor Pluto, who calls her "Small Lady," and is accompanied by her guardian cat Diana, daughter of Luna and Artemis. During the Black Moon Clan’s assault on Crystal Tokyo, Chibiusa mistakenly believes stealing the Silver Crystal will enable her to grow, inadvertently aiding the enemy. Burdened by guilt, she travels to the past using one of Sailor Pluto’s time-space keys. In the 20th century, Chibiusa conspires to take Usagi’s Silver Crystal, creating tension between them. She uses her toy Luna-P to hypnotize Usagi’s family into accepting her as their cousin, securing a place to stay. Her presence stirs jealousy in Usagi, particularly when Mamoru grows protective of Chibiusa, sensing a connection. Wiseman of the Black Moon Clan exploits Chibiusa’s guilt and loneliness, transforming her into an adult evil form called Black Lady using the Black Poison Crystal. As Black Lady, she assists in destroying Crystal Tokyo and attempts to seduce Tuxedo Mask, viewing him as separate from her future father. Sailor Pluto’s death breaks the brainwashing, triggering Chibiusa’s emotional maturity and awakening as Sailor Chibi Moon. This awakening allows her to physically grow to resemble a girl of ten or eleven. As Sailor Chibi Moon, she serves as the Pretty Guardian trainee of Love and Justice and leader of the Sailor Quartet. She transforms with the Pink Sugar Compact and attacks with Pink Sugar Heart Attack using the Pink Sugar Rod, and Abracadabra Pon with the Luna-P. She performs combined attacks such as Moon Princess Halation with Sailor Moon. Chibiusa returns to the 20th century during the Infinity arc to train with the Sailor Guardians. She befriends Hotaru Tomoe, whose chronic illness is eased by Chibiusa’s Silver Crystal. Hotaru is later revealed as the host of Mistress 9, who steals Chibiusa’s Silver Crystal, disconnecting Chibiusa’s soul. Hotaru’s soul safeguards Chibiusa’s until both are restored. Chibiusa is precocious and enjoys pulling pranks. She dreams of becoming a beautiful lady and finding her own prince. She favors the colors pink and red, and enjoys pudding, pancakes, and rabbits. She dislikes carrots and homemaking, and fears thunderstorms, ghosts, dentists, and needles. Initially socially awkward due to past teasing over her lack of powers, she gains confidence after awakening as a Sailor Guardian. Chibiusa appears in media such as the Sailor Moon SuperS movie, where she takes a central role in protecting children’s dreams from Queen Badiane and befriends a fairy named Perle. She helps save the day by uniting her heart energy with Sailor Moon.