I Seem To Recall It Loosely Like This:
Straight Woman Goes Into A Potion/Perfume Shop, Does Some Sort of Favor, Gets A Free Bottle. Uses Some, Then Gets Women Throwing Themselves At Her On The Bus, At The Office, Club etc., Then returns To Shop To Find Out Why. Gets Told She Was Given The Bottle For Men By Mistake, Offered The Other Bottle But Asks For More of The One She Had Gotten.
No Idea Where I Saw It, No Idea Who Wrote It, Just Half Remembered. Thanks For Letting Me Vent.