Hikaru Usada, performing as Rabi~en~Rose, is a 14-year-old human girl born on Earth on August 30, 1985. Her real surname "Usada" incorporates the Japanese word "usagi" (rabbit), reflecting her rabbit-themed persona. The similarity of her given name "Hikaru" to singer Hikaru Utada is officially deemed coincidental, as the character predates the singer's fame. Her parents support her idol aspirations by having her live independently, though she struggles financially, working multiple jobs including promoting her father's beauty salon "Charisma" by distributing tissues on the street. She transforms into Rabi~en~Rose using oversized dice, adopting a bunnygirl outfit featuring pink, white, and red attire, rabbit ears, a cotton tail, and dice-shaped hair ornaments. Unlike other kemonomimi characters in the franchise, she does not use animal-like speech suffixes. Rabi~en~Rose proclaims herself Dejiko's rival, frequently initiating conflicts to assert her status as the "idol of Gamers." Beneath her competitive and bossy exterior, her actions often conceal a desire for friendship with Dejiko, expressed through comedic or indirect gestures in manga narratives. During the *Ohanami Special*, she risks her life to retrieve a rare fruit to cure Dejiko's illness, only for Dejiko to dismiss her efforts and revert to rivalry upon recovery. Her background expands across the franchise: *Di Gi Charat Nyo!* reveals her French-Japanese heritage and attendance at Bobo Junior High School alongside Kiyoshi Omocha, whom she harbors a crush on. She later becomes a cheerleader at Princess School, where her cousin Akari Usada teaches. In *Winter Garden*, she achieves idol success yet retains unresolved feelings for Kiyoshi. Her character maintains a consistent arc of balancing rivalry with underlying kindness and persistent idol ambitions.