Couples' personalities converge over time to make partners more and more similar.
235
In medieval Italy, if a man was caught kissing a woman in public, he had to marry her whether he liked it or not.
456
In Korea, if you do not receive any gift on Valentine's day then all the singles go to Korean restaurants and eat black noodles to celebrate (or mourn) their single status.
28
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
In 2012, a Chinese man named Xiao Fan had a dress made out of 9,999 red roses for his girlfriend and then proposed - 9 in China means forever
16
Twenty nine percent of women spend more time shopping for shoes than they do looking for a life long mate.
737
Every year around 1 billion Valentine cards are sent. After Christmas it's a single largest seasonal card-sending occasion.
14
Historically, sweat has been an active ingredient in perfume and love potions.
309