In the film, Ruby and eleven other beautiful young women, all of whom suffer from allergies, were undergoing allergy "treatment" at Piz Gloria in Switzerland by James Bond's archenemy, Ernst Stavro Blofeld.
When Bond travels to Blofeld's clinic under the guise of Sir Hillary Bray, Ruby is immediately attracted to Bond. When Ruby is told not to mention her room number by Irma Bunt, she proceeds to write the number 8 on the inside of Bond's leg using her lipstick.
Later that evening Bond adventures into Ruby's room. Bond strips off the kilt that he is wearing, and Ruby is amused by it. They then make love but are interrupted when Blofeld's voice turns Ruby into a trance-like state. Bond arranges to meet Ruby the next evening, but when 007 walks over to the bed in Ruby's room, a waiting Irma Bunt knocks him out.