A teenager is a person aged 13-19. These years roughly correspond to adolescence, and still going through the process of physical maturation.
In modern society, the teenage years are considered a more "carefree" time than adulthood because teenagers do not yet have the responsibilities of the work world. For those men who are destined to be betabuxxers, though, the teenage years can be devoid of sexual opportunities because they do not yet have the ability to provide for a foid and get sex in return. Instead, foids go for the best men on the sports teams and much more rarely, prettyboys, but most of them don't pursue relationships.