Traditionally, guys have given boxes of chocolates to women on Valentines Day (the symbol of which is a "heart" which in reality looks more like an actual vulva than an actual heart). There is a biological reason for that: In an article entitled Top 10 Reasons Why Chocolate Is The World's Most Perfect Food, it states that chocolate contains tryptophan (the ingredient which, in turkey, causes folks to fall asleep on Thanksgiving Day) and phenylethylamine, which "reaches peak levels during orgasm".
That reminds me of the dessert they used to serve at the Baby Watson's fast food place near Harvard Square in Cambridge, where I worked as a pizza and sandwich cook. (Our New York-style cheesecake was originally made by a company called D'Aiuto's Pastry Corp.) Dennis Saide, the manager (from Lebanon) had his own unique names for products sold there. As I recall, his butterscotch brownies were called "gay bars", and the chocolate cheesecake brownies (like the one I just ate at Starbucks) were called "chocolate orgasms". His slogan, printed in yellow silkscreen ink on our brown aprons, was "Baby Watson: The creamiest thing you've ever had in your mouth". Something tells me that cheesecake was not the first thing that came into a lot of people's minds!
Of course, if the sex-like excitement from normal chocolate (like my favorite brand Cadbury) is not enough, one can always buy a piece of chocolate molded to resemble a real penis, complete with a sugary cream meant to look like a man's ejaculate. Such products can be bought from United Indecent Pleasures. It's not an American company; rather, the address seems to be in the Mediterranean islands. But if you're willing to pay for your very own chocolate dick, they are always willing to accomodate you. Just email them at email@example.com.