Maureen was an inmate of the New York Penitentiary who sought refuge from crazies in an old Chock full o'Nuts. She was a member of the Turks gang, formerly belonging to the Skulls gang.
She encountered S.D. "Snake" Plissken in the restaurant and asked him to take her with him out of the prison. As she prepared to kiss him, crazies breached the building and pulled her through the floor, killing her.
Behind the scenes[]
Maureen was played by Kurt Russell's then-wife, Season Hubley.
While the film identifies her solely as Girl in Chock full o'Nuts, the character is named Maureen in the shooting script and novelization.