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The lasting effect that occurs after having amazing sex. You will often have extreme happiness and ditziness. Your thoughts are all over the place. You will often blurt out random sex related thoughts. Will experience sudden hunger. There is a semi permanent smile on your face and speech will be slurred. Completely takes over your brain....earning the title of SEX BRAIN...
"Bro....I have a case of sex brain after boning last night! It was amazing...."
by MoMo2011 November 03, 2011