when your having sex with a grl and u ask her if she wants to be blind folded...she, thinking its so hot and kinky, says yes and allows the blind folding. you start having sex with her and then say a codeword(s) (ex. I LOVE YOU!) this is to let your friend that is in the closet/outside the room know that his time has come. you take your dick out and guid her to another position, where u procede to walk away and let your friend fuck her. You wait till shes about to come to say right into her ear...you can take the blind fold off... makes for a funny story the next day
John: Dude me and Joe pulled a switch-a-roo on Jane last night
Jake: Know way! Was she pissed?
John: Ask Joe, she bit his penis off when she took off the blindfold