Why do they want it justification for their actions?

 Sally performs seductively as she has just had a few lines of cocaine which makes her whole body tingle with energy. Her heart rushes fast, her eyes open wide her body moves swiftly. Her voice slurs making the performance extremely intriguing to watch. Sally wants to seduce Cliff  to earn money. She is a prostitute that is how she earns her money. Or possibly she is attempting to seduce Cliff to make her latest acquaintance jealous, to see if there are any emotions there for her or if she is just someone he sleeps with. She could also be trying to seduce Cliff in hope he will extend her social circle. As moving from England being a Bright young thing, then coming to Berlin with no trust fund and no acquaintances Sally must look for other ways to become successful. Sally dresses up in hope someone will cast her to perform in a show or a film. Cocaine helps to numb the fact she is a performer in a striper club.