You are a little brother. You live in the Objectist Utopia of Rapture. an underwater city built by Andrew Ryan. the businessman and Objectist who created Rapture as a place where the artist will not fear the censors, the scientist will not be bound by petite morality.

Rapture was built based on the concepts of free market and trickle-down economics.

but during the years a scientist named Briget Tannenbaum discovered Adam, a genetic substance that gives the user mutant superpowers. to gather the stuff

she and her business partner Frank Fontaine of Fontaine Futuristics have conditioned innocent Orphans to gather ADAM from corpses and bulking people to protect the children.

but later on, Fontaine was arrested for being a smuggler and was found dead. and Tannenbaum decided to protect the little sisters and brothers from Adam's hungry Spilcers even found a way of ridding the child of the conditioning. so now she takes care of the cured little ones in the old little sister opranage away from the splicers and Atlas.

you are a cured little brother. after finally being free from your joyful illusion conditioning you are now being taken care of by Tannenbaum. right now you were laying on your bed as the others play and do whatever.