Leo was part of a very talented family. Her father was a world-famous spelunker, while her mother, Emma Kliesen served as a G Corporation executive. Although Leo's father disappeared during an expedition when she was a child, she still wanted to follow in the family tradition and become a spelunker. Leo possessed a strong sense of character, thanks to a proper upbringing. Life was pleasant and relatively uneventful until one fateful day when her mother was killed by an unknown assailant. Depressed and filled with grief, she became incensed when the police called-off their investigation quickly and without explanation. She vowed to find the truth. During her investigation, the G Corporation's Kazuya Mishima materialized as a person of interest. The G Corporation was popularized at the time as a world hero, making it difficult to get close to Kazuya, and it looked as though Leo's quest had reached an insurmountable impasse. It was at this time that news of the Mishima Zaibatsu-sponsored The King of Iron Fist Tournament began to spread. Leo learned that Kazuya Mishima was scheduled to appear in person at the event. Realizing that this may be the only chance to take revenge against Kazuya, she decided to enter the tournament.