I shared an ex with a bbc bull and he was cool with our dicks touching in her mouth but when I stuck my dick in from behind for my first and only ever dvp attempt (because she was not into anal and knew I wanted to try it) from back in dvp, to get it to go, I have to push my dick against his first and push before it slides in. He let me think i was going to get my fantasy for all of 3 second or 2 good thrusts before he backed out and was not "comfortable" with the dpp so did not get to do it