The heroine of the story. To survive the harsh life on the streets, Hyun-Bin has been pretending to be male upon advice from an older girl, a prostitute. Hyun-Bin and her little brother, Pig, were forced to beg by a local gang. One day, the money they earned is stolen by one of the other gang members and when Hyun-Bin cannot explain to the gang leader what happened to the money, she and her brother are thrown out to spend the night outside in the freezing cold as punishment. Pig does not make it through the night and distraught Hyun-Bin runs away. By chance, she is taken in by a rich family, where she is trained to become a male bodyguard, she undergoes years of rigorous physical training as well as coaching to fix her speech and mannerisms to be boy-like. Finally, deemed to be worthy, she becomes Yae-Ha's bodyguard.