Hmmm.... tricky.
Okay I would sleep with all the female cast of the Twilight saga. All at once.
Throw in the female cast members of Tron, Scott Pilgrim vs. the World and uhm... oh gee being slutty is kinda hard on such a scale. Hmmmm.... oh... chuck in trueblood, how i met your mother and buffy the vampire slayers female cast too.
How did I do?