Funny how different the guys and the girls are. For me, if you're not stalking me or actively being flirty I won't notice, or I'll be so caught up trying to decipher the ambiguity of a girls behavior that I won't do anything.
Get into an argument about the objective superiority of one particular sexual act/position over another with him/her. Make sure to insist that it isn't just your opinion, but that your act/position is objectively superior based on a list of criteria that would establish the superiority of one sexual act over another. If you don't argue too persuasively (don't let the INTP concede your point whatever you do), Ne will take over and the next thing you know you'll have thoroughly finished both acts/positions and the INTP will be typing down the results into their laptop.