Zero eventually discovers that Stark had raped Gloria's mother after she broke up with him. She later blackmailed Stark with the threat of exposing him as a rapist, so he had her killed. However, she had already given birth to their daughter Gloria, who was discovered and raised by the hitman who killed her mother. Gloria grew up knowing that Stark was behind her mother's murder, and when her adoptive father contracted a terminal illness, she used the information to pay for medical treatment.