the act of giving and receiving oral sex/pleasure (at the same time) to/with a person of the opposite sex in a very intense and "nasty" manor.
girl: "I'm bored"
boy: "me too!"
girl: "wanna kill time?"
boy: "what did you have in mind?"
girl: "Brain Swap!!"
boy: "me too!"
girl: "wanna kill time?"
boy: "what did you have in mind?"
girl: "Brain Swap!!"
by Sdot.M June 26, 2009
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