Reformed slut

[Justin Bieber]

one who once practiced promiscuous sex, but has since dedicated her/himself to long-term conservative relationships. In America [reformed] sluts usually engage in promiscuous sex during the ages of 18-23, since these are also [prime years] for developing life long interests, reformed sluts will hardly have developed skills for any non-academic interests: cooking, dedication to engaging in sports, general taste in music, cleaning, outdoorsmanship, bilingualism, etc. This is usually referred to as [bimboism].
Likewise if one finds the above qualities in a guy/girl, then it is unlikely he/she is a reformed slut.