The word "genius" used in the sentence in this context most likely means a) someone who wrongly believes he is smart. b) a guardian spirit of a place or institution. c) a boring, dull fellow with little imagination. d) an exceptional natural capacity or talent for something.

"the only completely stationary object in the room was an enormous couch on which two young women were buoyed up as though upon an anchored balloon. they were both in white and their dresses were rippling and fluttering as if they had just been blown back in after a short flight around the house."