I find that roll playing is often a very good technique, if you want to disinterest a member of the opposite sex.  No, I don’t mean roll playing, like playing Doctor/Patient, or Dominatrix types games.  That kind of roll playing is not effective.  I find that the most effective form of roll playing, to get that member of the opposite sex disinterested, is Adventures of Dungeons and Dragons. Vampire the Masquerade is quite effective too.  Once you start talking about your character’s charisma points, or his double handed magic broad sword, or his ring of invincibility which he uses to conquer his enemies, any romantic feeling your counterpart had will usually disappear faster then a wizard who just put on his ring of invisibility. 

Once I was talking to this girl and told her that the kids who use to play
Dungeons and Dragons in my high school never really cared for me and would not let me play with them.  She exclaimed, “You mean even the Dungeons and Dragons kids were too cool for you????”  I could just feel the romance die in the air.
Star Wars merchandise also seems to turn off members of the opposite sex.  I, for example, have Star Wars sheets on my bed.  I am always ready in case I bring that unspecial person home.  Not only do I have the Star Wars sheets, but I have toy figures of Chewbacca and Darth Vader on my Desk, and a tape of a Star Wars movie, on queue, at all times, for her viewing pleasure.  Believe me, this works better than porno.  Usually, I will have the tape queued up to the lite saber duel between Darth Maul, Obi-Wan Kenobi, and Qui-Gon Jinn in Episode I, which was a really cool duel, or the lite saber duel between Luke Skywalker and Darth Vader in the Empire Strikes Back, where Luke gets his hand cut off.  Just lay on the sheets, and play the movie, and believe me, your counterpart will be out of there faster than you can say Chewbacca the Wookie.
What a Wookie!!!!!!!!!!!!!