Greig's defense attorney, Kevin Reddington, maintained that Greig knew little to nothing about Bulger's crimes when she left Boston with Bulger in 1995.
Greig and Bulger were arrested in Santa Monica in June.
Prosecutors portrayed Greig as an eager partner to Bulger, who willingly went on the run with him and actively helped him elude authorities for more than 16 years.
Assistant U.S. Attorney James Herbert asked FBI agent Michael Carazza about conversations Greig allegedly had with her hairdresser in Santa Monica about her relationship with Bulger, whom she referred to as her husband.
Carazza said Greig told the hairdresser she "liked bad boys."
"She said she knew her husband was a bad boy when she married him, but he's mellowed out now," Greig told the hairdresser, Carazza said.
Carazza acknowledged that members of a family who befriended the couple said Bulger was harsh and controlling, and treated Greig like a servant.
Magistrate Judge Jennifer Boal did not immediately rule on whether to keep Greig behind bars while she awaits trial on a charge of harboring a fugitive.
The Associated Press contributed to this report.