My first "manual" was "Everything you always wanted to know about sex, but were afraid to ask". My Mom gave it to me. Good book, but lacking in the joy area. My ex (and second) hubby taught me the joy of sex. Even tho our marriage ended, I will be eternally grateful. My first "O" was at age 28, with him.
Sex is still so full of mystery for many people and fraught with anxiety (performance mostly), that many miss out on the joy. They tend to be to damned serious. North Americans seem to be more "uptight" than other nations concerning the human body and sex. Too bad, really.