I picture Zaeed as the leader of a gang of roadside bandits and Kasumi as a master theif who sometimes does the occasional odd job for him since they are old friends. They met years prior when Kasumi was a young upstart thief that tried to steal Zaeedís jewel encrusted broadsword but Zaeed caught her in the act and managed to briefly subdue her, impressed with the young girls spirit he offered her a place in his gang and she stayed with him for awhile before going out on her own to pursue bigger and better heists.
Kasumi- pretty much just took her mass effect outfit and gave it a medieval makeover, she wields dual curved daggers in battle.
Zaeed- also didnít change much aside from removing the sci-fi elements, and removed his artificial eye (at least I think itís artificial in ME). He lost it when he he killed the former gang leader in a duel.
Only two more characters left to go, one will be Joker as Iíve already said and heíll be paired with a surprise partner to conclude the dragon effect series.