Also known as BBF. Your bad behavior friend lives on the other side of the country and you rarely talk other than by email or text now so you can confide your deepest secrets, desires and transgressions with no shame!
You both are surrounded by people that you hide the true extent of your sickness from and therefore have only each other to let your guard down with.
After a night of dancing, Meg found herself secretly having drunk sex with her best friend's boyfriend. Meg went for lunch the next day with her best-behavior friend Rachel and when Meg recounted her night to Rachel, the sexual elements were removed. But when she texted her bad-behavior friend later all the sweaty details were there!