Rosza comes from the citystate of Cassezo, located in the Heel of Accitaine; orphaned early on and grown wild, she became a gang enforcer in her early teens, showing flair for swashbuckling violence and daring, and quickly became known as a alluring femme fatale with a great sense of style. She is one of the Gunslingers who subscribe to a philosophy known as The Way of the Gun, and like many Cassezan Gunslingers believe that firearms are a weapon with mystical properties, much like a fencing master believes his sword is imbued with special power.

She teamed up with a young up and coming Gunslinger called Zeru Otxoaand took him under her wing, and they had a number of adventures and exploits that raised a few eyebrows including the famous (in Cassezo at least) Stand of the Benevolent Twelve, but ultimately a disagreement between them over the division of spoils after a job ended in violence, and she fled for parts unknown, leaving her erstwhile friend and lover bleeding out; he survived (somehow), and now perhaps seeks revenge (and the loot of course).

Her almost lifeless body was taken by the Vampire Jalako and now she has been turned into a True Vampire, seemingly embracing her new existence as a consort and cohort of the First of the Vampires.

In life Rosza was mercurial, tempestuous, exciting and vibrant, but also superstitious and given to bouts of temper and whimsy that lead her to act before thinking at times; what her new outlook is after her becoming a Vampire is unknown, but it surely can’t be a good development.