What is the theme in Small World by David Lodge?

Sex is a major theme in the story. Small World is permeated with sexual tension. A repressed, napve young man determined to preserve his virginity until marriage falls in love with a beautiful, sensual teaser. His strong Catholic beliefs torment him when he must descend into the world of pornography seeking his errant cousin and, as he incorrectly believes, his beloved. An older virgin is depicted as choosing this lifestyle because of the perceived ill effects marriage has had on colleagues' careers