Alexis Simpson and Dominique Frazier never got along while living together at Bowie State University, according to attorneys, who on Tuesday described the roommates' troubled relationship that quickly boiled over in September 2011 into a physical confrontation that left Frazier dead and Simpson charged with murder.

Prosecutors say Simpson, then a transfer to Bowie State beginning her sophomore year, chose to aggressively pursue Frazier on the night of Sept. 15, after a disagreement about music being played on an iPod escalated to the point where the two women ferociously traded blows.

Assistant State's Attorney Christine Murphy told jurors during opening statements in Upper Marlboro that at least twice during that night, Frazier had retreated to her bedroom with friends in order to calm down and avoid more confrontation with Simpson.

But Simpson, who was indicted for murder in October 2011, instead went after Frazier in the dorm room with a knife, stabbing Frazier's arm and slicing her neck, a cut that severed Frazier's trachea and jugular vein, Murphy said.

Simpson twice came banging on Frazier's door prior to the final confrontation, yelling, "Come out here, I'm not done," according to Murphy.

"When faced with multiple options, look what choices the defendant made," she told the jury.

But defense attorneys argued that Frazier was a more-than-willing participant in the fight with Simpson, detailing a pattern of bullying that began shortly after the young women moved in together at the beginning of the 2011-12 school year.

Frazier sought a confrontation with Simpson, said defense attorney Christopher Griffiths, setting up a showdown that left Simpson outnumbered and scared.

And while in her dorm room, Frazier herself picked up a knife before putting it away at the urging of a friend, Griffiths argued.

The bullying became too much for Simpson, who tried to be transferred to a different room but was denied by a property management company, according to Griffiths.

And Simpson made the deadly cut with her head down while being attacked by three women in the suite, including Frazier, he said.

"She acted in self-defense, and she had no choice," Griffiths said in his opening statement. "When the cutting happened, she had been beaten by three girls who had been looking for an opportunity to get her for weeks."

The trial is expected to wrap up this week.