As in the guy you would like to date if something happens to your current boyfriend/crush. This is sort of like insurance if your old boyfriend breaks up with you. (The guy used for your rebound)
Girl: "I don't care if he dumps me I've still got my BBF."
BBF stands for Bed Baggy Fuck, or Fucking. This is the act of putting a plethora of lubrication in a sandwich zip-loc baggy. After you do this, make sure it spreads, then go to your bed and life up your mattress slightly. Place the back 75% of the bag under the matress so the open end is sticking out. open baggy, insert erction, and proceed to fucking.
Back Burnner Friend
Someone to use in replacement or back up in order to accommodate you when your real friends are not available . Someone to keep behind our prestigious social network. BBF requires only minimal insignificant attention, sufficient to keep sustain that friendship.
"My buds MIKE and MANUEL are out of town this weekend, so I'm just hanging out here with one of my BBF"