Aimed at adolescents and young adults ages 16-22, S.E.X. is also for parents, teachers, and all others, young or old, interested in the physical health and well-being of youth today. S.E.X. is sex-positive and inclusive, encouraging young adults of any and all body type and gender orientation to take ownership of and enjoy their bodies and sexuality in a manner responsible and respectful of others. Its author Heather Corinna is founder of the widely recognized grassroots sexuality education and support organization and website Scarleteen.com.

In her book, Corinna points out that sex isn't just about your genitals or partnered heterosexual intercourse. It's a mix of different things--physical, chemical, emotional, intellectual, social, and cultural. Corinna educates the reader about the essentials of one's body; issues surrounding body image; sex with self and sex with others; healing from abuse; pregnancy and birth control; gender orientation and sexuality identity; and more. As Minnesota Women's Press writes in a product review, "S.E.X. itself is revolutionary as a feminist, GLBT-friendly and overall progressive collection of sexual education material"