Mariam was the caretaker/henchwoman of Baby-Doll.
Mariam posed as a "mother" to Baby-Doll when she passed herself off as a little girl, and as a bodyguard and henchwench after she kidnapped her old cast mates. Also, when Tod Baker attempted to leave Doll's hideout, she kicked him back to the set, showing to be very loyal to her boss.
Her fighting skills were on par with Batman and Robin, the latter of which even praised her skills. While she was capable, she was eventually knocked out when Batman threw his rope around her ankle and slung her into a set piece, knocking her out.