A brief article on LiveScience today reports the opinion of researcher Alfonso Manas at the University of Granada, that this statuette represents a female gladiator (gladiatrix) in the moment of victory, raising her curved short sword (the sica, a popular weapon with arena combatants) over her defeated foe.
If Manas proves to be correct, this will be the second depiction of female gladiators to survive from Roman antiquity. For the record, the other known depiction also depicts the ladies topless, so this may be a worthwhile consistency to note.
Provenance of the statue is unknown, but it is currently held in the Museum für Kunst und Gewerbein Hamburg, Germany.
Links below to a little more evidence of female gladiators in the Roman empire.