A vain, ignorant, and superficial middle-aged woman who unsuccessfully attempts to make herself look youthful by caking on make-up and by wearing the trendy clothing of college-aged females. This phrase is actually an older popular characterization which one occasionally encounters in classic literature and especially in Golden Age British mysteries.
Check out that noxious oldheifer -- laced mutton of The First Water.
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi