{NSFW} Etiquette?

So your a man and you start seeing a new lady friend and things turn sexual for the first time. We take a trip down BJ lane. What is your etiquette here when it comes to the grand finale guys? Girls what is preferential to you? Do you give warning, just let it happen, hold on tight and wait or take your cue from the girl? I have always been curious how others approach this?

Obviously, it’s late and the mind boggles.