Jamyra Gallmon pleaded guilty to second degree murder while armed for stabbing David Messerschmitt to death in a room at The Donovan Hotel in February.
Gallmon met the victim through a Craigslist ad he posted soliciting other men and intended to rob him.
Gallmon's roommate, Dominique Johnson, pleaded guilty to conspiracy to commit robbery. Prosecutors said Johnson knew Gallmon had planned to rob someone and waited outside the hotel for her.
The victim's widow cried in court Thursday as prosecutors described the wounds to Messerschmitt's body. He was stabbed approximately seven times, authorities said.
The women only got away with $40 in cash, a SmartTrip card and the victim's cell phone.
Gallmon faces 18 to 25 years in prison and Johnson faces up to five years in prison. Sentencing is August 14.
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