me and my friend have 2 friends with benefits (one for him one for me). we are going to vegas together and staying in the same room. we tell our FWB's we want to fuck them hard straight up (that is our comfort level with our FWB's). My question is how do we insinuate them to make out while we have sex with our FWB (no swapping) just them making out while we do it from behind. Does anyone have some suggestions on how to make this happen with two straight girls?