Sex Education, as the term clearly indicates, refers to education which is based on human sexual behavior. Parents, schools or caretakers offer it in some parts of the world to educate the children, who are stepping into their adolescence. If formally received, sex education is either taught as a full course at high school or junior high school level or in biology, health, home economics classes.
No one rejects, dislikes, or avoids pleasure itself, because it is pleasure, but because those who do not know how to pursue pleasure rationally encounter consequences that are extremely painful. Nor again is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure.
To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it?