You choose to laugh and say something complimentary. 

Owen grins, and responds, "Well thanks.  It's always nice to meet sane fans."  With that he gives a little laugh, and glances once again at your exposed body.

"So," he breathes, "You busy?  I'm going to a P Diddy party right now, and I have a feeling that you would fit right in."

Oh my gosh!  Owen Wilson just invited you to one of the famous Puff Daddy parties!!  But he also said that you would fit in there... you've seen the pictures.  All of those girls are groupies who will do anything for celebrity attention.  Does he really think that of you?  What to do... what to do!?
Meeting Owen Wilson 
What will you DO?!?  Will you...
Ignore the fact that you look like a slut, and agree to go!  Heck, this could be the start of something beautiful.
Get angry at his judgment of you, and say something like "Just because a woman is liberated in her manner of dress does not mean that she is loose like the women you find at those stupid parties!"
or will you...
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