Leo was the first-born daughter of a high-class evil shinobi family, her father being the principal of Foundation Star Cross Academy. She was chosen as the Heiress to the family's vast wealth, while Hyōki was left with the shinobi lineage.

A natural socialite and brimming with charisma, Leo easily fit into the high-class lifestyle. She charmed and attracted everyone around her with her beauty and class, so much so that she always had a line of suitors constantly vying for her affection. Her best friend and bodyguard, Ginrei, wasn't immune to Leo's charm and harbored feelings for her.

Leo lived a mostly cozy and stress-free life, showered in praise from both her parents and friends while enjoying her vast wealth. She was once close to Hyōki, often spending their free time playing games, but a rift formed in their relationship once Hyōki was caught into her duties as a shinobi.