The idea that two semi-attractive females have an increased sexual desirability due to being identical twins. (It is similar in concept to the cheerleader effect).
Guy 1: yo check it out hot twins at our 9 o'clock. I'd do 'em.
Guy 2: you mean those two semi-ugly bitches? hell no!

Identical Twin Theory in effect.
by GamerGuy631- June 27, 2009
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