Berkley Medallion, New York, 1966
(price: 60c; 160 pages)

The blurb on the back:

Twenty-one plus and still a virgin - yes, that's Georgy Girl. She was too much of an ugly duckling to be desired by men, and had almost given up hope.
But what would happen if ... her very beautiful roommate got pregnant and then got married, and then her husband realized that he preferred Georgy? Quite an unusual ménage à trois...
Further complicated by James, who most certainly did want Georgy, only he was old enough to be her father, and already married. The result is a wildly hilarious, off-beat novel, which has just been made into a sensational motion picture.