Secret blondie.
When you dye your hair a darker (and usually duller) color, to make people think you are either smarter or not as wild as they thought (because everyone gets tired of blond jokes, and rude pigs)
Girl: "I'm busted."
Girl's best friend: "Busted how?"
Girl: "My boyfriend saw my dye fading, now he know I'm a secret blondie."
Girl's best friend: "Busted how?"
Girl: "My boyfriend saw my dye fading, now he know I'm a secret blondie."