I just read this somewhere...once you give a chocolate as a gift you must match the chocolate to the reciever's personality:

chocolate
Simple. laidback and flexible.. the cool type

white chocolate
shy, sweet, caring, clumsy, child-like and if you're a girl.. you are a type who is super girly...

dark chocolate
secretive, mysterious, silent-type, unpredictable.. can also be shy in a darker way haha.. in anime i think he or she is kinda "yandere"

chocolate with diff. toppings

talkative, energetic, mostly extroverted, the life of the party.