Hmmm, if it was anyone in the world now then I'd probably pick someone I know in order to provide potent masturbatory memories of them. All my favourite pornstars/models provide enough visual stimulus/materials for me as it is, there aren't any non nude celebrities I give a shit about really. In other words, I'd probably only pick someone who's tits I haven't seen, that I really want to. However in this hypothetical situation if anywhen is also incorporated into the equation, then it's Pam Anderson circa 1995 without any doubt or hesitation whatsoever. That encounter would definitely leave me with memories that would make me wank over Pamela even more than I do now which is LOTS AND LOTS.
Oh, sorry. I meant to say Susie Diamond.